Title of Invention

SUPPORTED COMPOSITE PARTICLE MATERIAL, PRODUCTION PROCESS OF SAME AND PROCESS FOR PRODUCING COMPOUNDS USING SUPPORTED COMPOSITE PARTICLE MATERIAL AS CATALYST FOR CHEMICAL SYNTHESIS

Abstract A supported composite particle material comprises: a composite particle formed of an oxidized nickel and X (wherein X represents at least one of elements selected from the group consisting of nickel, palladium, platinum, ruthenium, gold, silver and copper); and a support on which the composite particle is supported, the supported composite particle material having a supported layer in which the composite particle is localized.
Full Text

SPECIFICATION
SUPPORTED COMPOSITE PARTICLE MATERIAL, PRODUCTION PROCESS OF
SAME AND PROCESS FOR PRODUCING COMPOUNDS USING SUPPORTED
COMPOSITE PARTICLE MATERIAL AS CATALYST FOR CHEMICAL SYNTHESIS
Technical Field
[0001 ]
The present invention relates to a supported composite particle material in
which composite particle formed of an oxidized nickel and X (wherein X represents at
least one type of elements selected from the group consisting of nickel, palladium,
platinum, ruthenium, gold, silver and copper) is supported onto a support, a process
for producing the supported composite particle material, and a process for producing
compounds, using the supported composite particle material as a catalyst for
chemical synthesis.
Background Art
[0002]
Nickel or nickel compounds are widely used as catalysts for chemical synthesis
such as in oxidation reactions, reduction reactions, hydrogenation reactions or the like.
Conventional examples of the use of nickel or nickel compounds in oxidation
reactions may include: (1) an alcohol oxidation reaction in which nickel peroxide
(NiO2) is used as a stoichiometric oxidizing agent (Non-Patent Document 1), (2) an
alcohol aerobic oxidation reaction using Ni-AI hydrotalcite as a catalyst (Non-Patent
Document 2), (3) an alcohol aerobic oxidation reaction using Mg-AI hydrotalcite
containing Ni(ll) as a catalyst (Non-Patent Document 3), and (4) an alcohol aerobic
oxidation reaction using nickel peroxide (NiO2) nanoparticles as a catalyst

(Non-Patent Document 4).
As described in (1) above, highly oxidized nickel peroxide has a higher level of
oxidizing power than nickel oxide, and has long been known to be able to oxidize
various alcohols stoichiometrically. This type of nickel peroxide has not been
obtained in pure form or in the form of an anhydride, there are many aspects of its
structure that remain unclear, and is also said to be a nickel oxide that has adsorbed
oxygen. However, since nickel peroxide is extremely useful as a stoichiometric
oxidizing agent, if it were possible to catalytically generate active oxidizing active
species using moleculer oxygen for the oxidizing agent, it would be able to be applied
to aerobic oxidation of numerous organic substrates.
Catalytic alcohol aerobic oxidation reactions have been realized in recent years
as a result of various modifications and improvements to nickel-based catalysts. The
nickel-hydrotalcite-based catalysts described in (2) and (3) above realize highly
efficient activation of moleculer oxygen by compounding Ni with dissimilar metal
elements (such as Al or Mg), thereby achieving aerobic oxidation with a
heterogeneous nickel catalyst. In these catalysts, Ni functions as an oxygen
activation site as a result of compounding Ni with a dissimilar metal element, and is
thought to result in the formation of peroxo species serving as reactive species on the
Ni. In addition, in the method described in (4) above using nickel peroxide, the
reaction has been reported to proceed catalytically as a result of forming the nickel
oxide into nanoparticles.
In the chemical industry, the use of nickel and nickel compounds is not limited to
alcohol oxidation reactions, but have also been shown to be widely effective in various
reactions such as various oxidation reactions, reduction reactions and hydrogenation
reactions, as well as in catalysts for purification of automobile exhaust gas and in
photocatalysts.

[0003]
Non-Patent Document 1 :J . Org. Chem., 27 (1962) 1597
Non-Patent Document 2 : Angew. Chem. Int. Ed., 40 (2001) 763
Non-Patent Document 3 : J. Mol. Catal., A236 (2005) 206
Non-Patent Document 4: Appl. Catal., A282 (2005) 25
Disclosure of the Invention
[0004]
Problems to be Solved by the Invention
However, the known methods described above do not necessarily have
adequate target product selectivity or catalyst activity, and are unlikely to be
considered as industrially advantageous methods. In addition, in consideration of
the objective of realizing a reduction in the amount of active ingredient used and high
reactivity, nickel and nickel compounds used as catalysts are generally used by
dispersing and supporting onto a support in order to increase specific surface area
and enhance usage efficiency during use as catalyst components. Although
supports on which nickel or nickel compounds are supported are of various types
depending on reaction characteristics and application, these supports have problems
such as not always being able to obtain satisfactory reaction activity or catalyst active
ingredients being susceptible to dropout from the support depending on the
distribution of catalyst components within the support.
The present inventors conducted extensive studies on the supported composite
particle material of the present application, in which composite particles comprising
oxidized nickel and X (wherein X represents at least one of elements selected from
the group consisting of nickel, palladium, platinum, ruthenium, gold, silver and copper)
are supported onto a support, based on the premise of practical application thereof in

an industrial process. As a result, in the case of using as a catalyst for chemical
synthesis, since a supported composite particle material in which composite particles
are uniformly supported on the inside of a support inhibit diffusion of reaction raw
materials and reaction products due to the resistance of pores inside the support,
composite particles supported inside a support are not used effectively, and such
supported composite particle material has been clearly demonstrated to prevent the
obtaining of catalysts that are not necessarily satisfactory from the viewpoint of
reaction activity. In addition, the composite particles supported onto the outer
surface of support particles were determined to have problems such as a loss of
activity due to concealment of active sites due to the adsorption of reaction
by-products and accumulation of toxic substances depending on the type of reaction
or type of reaction apparatus and the like, and a loss of catalyst activity due to
composite particles dropping out from the support due to wear caused by collisions
between support particles and between support particles and reactor walls and the
like.
[0005]
With the foregoing in view, an object of the present invention is to provide a
supported composite particle material that maintains high reactivity for a long period of
time by stably supporting composite particles comprised of an oxidized nickel and X
(wherein X represents at least one of elements selected from the group consisting of
nickel, palladium, platinum, ruthenium, gold, silver and copper) on a support, a
process for producing the supported composite particle material, and a process for
producing compounds using the supported composite particle material as a catalyst
for chemical synthesis.
Means for Solving the Problems

[0006]
As a result of conducting extensive studies on the above-mentioned problems,
the present inventors found that, in a supported composite particle material
comprising composite particles comprised of an oxidized nickel and X (wherein X
represents at least one of elements selected from the group consisting of nickel,
palladium, platinum, ruthenium, gold, silver and copper) and a support on which the
composite particles are supported, by controlling the distribution of the composite
particles within the support and forming a supported layer in which the composite
particles are localized within a specific range, the above-mentioned problems can be
resolved, thereby leading to completion of the present invention.
[0007]
Namely, the present invention is as described below:
[1] A supported composite particle material comprising:
a composite particle formed of an oxidized nickel and X (wherein X represents at
least one of elements selected from the group consisting of nickel, palladium, platinum,
ruthenium, gold, silver and copper); and
a support on which the composite particle is supported,
wherein the supported composite particle material comprises a supported layer
in which the composite particle is localized.
[2] The supported composite particle material according to item [1], wherein the
supported layer in which the composite particle is localized is present in a region
extending from a surface of the supported composite particle material to 40% of an
equivalent diameter of the supported composite particle material.
[3] The supported composite particle material according to item [1] or [2], wherein
the equivalent diameter of the supported composite particle material exceeds 200 µm,
and the supported layer in which the composite particle is localized is present in a

region extending by 80 µm from an outer surface of the supported composite particle
material.
[4] The supported composite particle material according to item [1] or [2], wherein
the equivalent diameter of the supported composite particle material is 200 µm or less,
and the supported layer in which the composite particle is localized is present in a
region extending from the surface of the supported composite particle material to 30%
of the equivalent diameter of the supported composite particle material.
[5] The supported composite particle material according to any one of items [1] to [4],
comprising an outer layer substantially free of the composite particle on an outside of
the supported layer in which the composite particle is localized.
[6] The supported composite particle material according to item [5], wherein the
outer layer is formed at a thickness of 0.01 to 15 µm from the outer surface of the
support.
[7] The supported composite particle material according to any one of items [1 ] to [6],
wherein the composite particle has a mean particle diameter of from 2 to 10 nm.
[8] The supported composite particle material according to any one of items [1] to [7],
wherein a compositional ratio of nickel and X in the composite particle, in terms of an
atomic ratio of Ni/X, is from 0.1 to 10.
[9] The supported composite particle material according to any one of items [1 ] to [8],
wherein the composite particle has a core formed of X and the core is coated with
oxidized nickel.
[10] The supported composite particle material according to any one of items [1] to
[9], wherein the support is formed of an aluminum-containing silica-based composition
containing silica and alumina.
[11] A process for producing a supported composite particle material in which the
composite particle formed of an oxidized nickel and X (wherein X represents at least

one of elements selected from the group consisting of nickel, palladium, platinum,
ruthenium, gold, silver and copper) is supported onto a support, comprising:
a first step of obtaining a mixture at a temperature of at least 60°C by mixing an
aqueous slurry containing a support on which is supported an oxide of at least one of
basic metals selected from the group consisting of alkaline metals, alkaline earth
metals and rare earth metals, and an acidic aqueous solution of a soluble metal salt
containing nickel and the X; and
a second step of heat-treating a precursor contained in the mixture.
[12] The process for producing the supported composite particle material according
to item [11], wherein the aqueous slurry further comprises a salt of at least one of
basic metals selected from the group consisting of alkaline metals, alkaline earth
metals and rare earth metals.
[13] The process for producing the supported composite particle material according
to item [11] or [12], wherein the aqueous slurry further comprises a soluble aluminum
salt.
[14] A process for producing carboxylic acid ester comprising:
reacting an aldehyde and an alcohol in the presence of oxygen by using the
supported composite particle material according to any one of items [1] to [10] as a
catalyst.
[15] The process for producing carboxylic acid ester according to item [14], wherein
the aldehyde is selected from acrolein, methacrolein or a mixture thereof.
[16] The process for producing carboxylic acid ester according to item [14] or [15],
wherein the alcohol is methanol.
Advantageous Effects of the Invention
[0008]

The supported composite particle material according to the present invention is
able to maintain high reactivity over a long period of time by efficiently using
composite particles by stably supporting composite particles comprised of the
oxidized nickel and X (wherein X represents at least one of elements selected from
the group consisting of nickel, palladium, platinum, ruthenium, gold, silver and copper)
on a support.
Brief Description of the Drawings
[0009]
FIG. 1 shows the results of X-ray analysis using an X-ray microprobe of a
particle cross-section of the supported composite particle material of Example 1;
FIG. 2 shows the results of X-ray analysis using an X-ray microprobe of a
particle cross-section of the supported composite particle material of Example 2;
FIG. 3 shows the results of X-ray analysis using an X-ray microprobe of a
particle cross-section of the supported composite particle material of Comparative
Example 1; and
FIG. 4 shows the results of X-ray analysis using an X-ray microprobe of a
particle cross-section of the supported composite particle material of Comparative
Example 2.
Best Mode for Carrying Out the Invention
[0010]
The following provides an explanation of the best mode for carrying out the
present invention (to be referred to as "the present embodiment"). The following
embodiment is exemplified for explaining the present invention, and is not intended to
limit the present invention to only this embodiment. The present invention can be

carried out in various forms without deviating from the gist thereof.
[0011]
[Supported Composite Particle Material]
The supported composite particle material according to the present embodiment
comprises composite particles comprised of an oxidized nickel and X (wherein X
represents at least one of elements selected from the group consisting of nickel,
palladium, platinum, ruthenium, gold, silver and copper) and a support on which the
composite particles are supported, and has a supported layer in which the composite
particle is localized.
[0012]
The term "supported layer in which the composite particles are localized" used
herein refers to a region in the support in which the composite particles are
concentrated. In the supported composite particle material according to the present
embodiment, since the composite particles are not randomly supported in the support,
but rather selectively supported in a fixed region, this region is generically referred to
as a "supported layer in which the composite particles are localized". In the
supported composite particle material, since a region is a "supported layer in which
the composite particles are localized" provided the composite particles are
concentrated in a fixed region as compared with other portions, which region is a
"supported layer in which the composite particles are localized" can be determined by
X-ray microprobe analysis to be described later or from secondary electron reflected
images obtained with a high-resolution scanning electron microscope. The
supported layer in which the composite particles are localized is preferably present in
a region extending from the surface of the supported composite particle material to
40% of the equivalent diameter of the supported composite particle material. If the
supported layer in which the composite particles are localized is present in this region,

the effects of diffusion rates of the reactants within the support are reduced, which
tends to improve reaction activity.
[0013]
The supported composite particle material according to the present embodiment
can have various sizes and various shapes such that the substantial thickness of
particle diameter is on the µm to cm order. Specific examples of the shape of the
supported composite particle material may include various shapes such as spheres,
ovals, cylinders, tablets, hollow cylinders, plates, rods, sheets, honeycombs or the like.
The shape of the supported composite particle material can be suitably changed
according to the reaction form, and in a fixed bed reaction, for example, hollow
cylindrical or honeycomb-shaped particles are selected due to their low pressure loss,
while spherical particles are typically selected under conditions of suspending in a
liquid phase slurry.
[0014]
The term "equivalent diameter" used herein refers to the diameter of spherical
particles, or in the case of irregularly shaped particles, the diameter of a sphere
having an equal volume as the particles or having a surface area equal to the surface
area of the particles. Equivalent diameter is measured by measuring the mean
particle diameter (volume-based) using a laser diffraction/scattering particle size
distribution measuring apparatus and using the resulting value as the equivalent
diameter. Alternatively, number average particle diameter as measured with a
scanning electron microscope (SEM) can also be used to represent equivalent
diameter.
[0015]
The thickness of the supported layer in which the composite particles are
localized is selected to an optimum range according to the thickness of the support,
particle diameter, type of reaction and reaction form. Furthermore, since the

"equivalent diameter of the supported composite particle material" is usually the same
as the "equivalent diameter of the support", the "equivalent diameter of the supported
composite particle material" can be determined from the equivalent diameter of the
support.
[0016]
For example, in the case of using a support of a size such that the thickness of
the support exceeds 200 µm (for example several mm or more), the supported
composite particle material is generally used in a liquid phase reaction having a
comparatively slow reaction rate or in a vapor phase reaction. Thus, by providing a
region in which the active component in the form of composite particles extend from
the surface of the supported composite particle material to 40% of the equivalent
diameter of the supported composite particle material, and a layer in which the
composite particles are supported to 80 µm from the outer surface of the supported
composite particle material but not supported inside the supported composite particle
material, the supported composite particle material can be obtained that is resistant to
the effects of the diffusion rates of the reactants. As a result, the composite particles
can be used effectively.
[0017]
On the other hand, in the case the thickness of the support is 200 µm or less, the
composite particles are preferably supported in a region extending from the surface of
the supported composite particle material to 30% of the equivalent diameter of the
supported composite particle material. In the case of using in a liquid phase reaction
in particular, the support was conventionally designed to have a small particle
diameter in line with the reaction due to the effects of the reaction rate and the
intrapore diffusion rates of reactants within the support. In the present embodiment,
a highly active supported composite particle material can be obtained without

reducing the particle diameter of the support by reducing the thickness of the
supported layer in which the composite particles are localized. Namely, according to
the present embodiment, it becomes easy to separate the catalyst by settling, thereby
resulting in the advantage of enabling separation to be carried out using a
small-volume separator. However, if the volume of the portion of composite particles
in the supported composite particle material that are not supported becomes
excessively large, the volume not required by the reaction per container increases,
thereby resulting in waste. Thus, it is preferable to set the particle diameter of the
support, the required thickness of the supported layer in which composite particles are
localized and the thickness of the layer in which composite particles are not supported
according to the reaction form.
[0018]
The supported composite particle material may also have an outer layer
substantially free of composite particles on the outside of the supported layer in which
composite particles are localized. The outer layer is preferably formed at a thickness
of 0.01 to 15 µm from the outer surface of the support. As a result of providing the
outer layer within this range, the supported composite particle material can be used as
a catalyst strongly resistant to catalyst poisoning that inhibits the loss of composite
particles due to abrasion in reactions using reactors such as a fluidized bed, bubble
column, stirring reactor or other reactor for which there is the risk of friction of catalyst
particles, and in reactions in which there is accumulation of catalytic poisons. In
addition, since the outer layer can be controlled to be extremely thin, large decreases
in activity can be suppressed.
[0019]
The thickness of the outer layer substantially free of composite particles is
selected to an optimum range according to the reaction characteristics, physical

properties of the support, loading of composite particles and the like, and is preferably
from 0.01 to 15 µm, more preferably from 0.1 to 10 µm, and even more preferably
from 0.2 to 5 µm. If the thickness of the outer layer (composite
particle-non-supported layer) exceeds 15 µm, although there is no change in the
effect of improving catalyst life when using the composite particles as a catalyst, this
leads to a decrease in catalyst activity. If the thickness of the outer layer is less than
0.01 urn, susceptibility to loss of catalyst particles due to abrasion tends to increase.
[00020]
In the present embodiment, the term "substantially free of composite particles"
used herein refers to the substantial absence of a peak indicating the distribution
oxidized nickel and X (wherein X represents at least one of elements selected from
the group consisting of nickel, palladium, platinum, ruthenium, gold, silver and copper)
having a relative intensity of 10% or more in X-ray microprobe analysis to be
described later or in secondary electron reflected images obtained with a
high-resolution scanning electron microscope.
[0021]
The composite particles of the present embodiment are particles comprised of
an oxidized nickel and X (wherein X represents at least one of elements selected from
the group consisting of nickel, palladium, platinum, ruthenium, gold, silver and
copper).
[0022]
Preferable examples of the oxidized nickel may include nickel oxides formed by
bonding nickel and oxygen (such as Ni2O, NiO, NiO2, Ni3O4 or Ni2O3), and composite
oxides containing nickel such as nickel oxide compounds formed by bonding nickel
and X and/or one or more types of other metal elements and oxygen, or a solid
solution or mixture thereof.
[0023]

The term "nickel oxide" used herein refers to a compound containing nickel and
oxygen. Nickel oxides may include the previously exemplified Ni2O, NiO, NiO2,
Ni3O4 or Ni2O3 or hydrates thereof, hydroperoxides of nickel containing an OOH group,
peroxides of nickel containing an O2 group, and mixtures thereof.
[0024]
In addition, the term "composite oxide" used herein refers to an oxide containing
two or more types of metals. The term "composite oxide" used herein refers to an
oxide in which two or more types of metal oxides form a compound, and although it
includes multiple oxides not containing an ion of an oxoacid as a structural unit (such
as pervoskite oxides and spinel oxides of nickel), it refers to that having a broader
context than multiple oxides, and includes all oxides in which two or more types of
metals are compounded. Oxides in which two or more types of metal oxides form a
solid solution are also within the scope of composite oxides.
[0025]
The present inventors found that, in the case of using the supported composite
particle material according to the present embodiment as a catalyst for synthesis of
carboxylic acid esters, by compounding nickel oxide with X, the inherent catalytic
ability of nickel oxides having oxidative esterification activity can be brought out and a
remarkably high level of catalyst performance can be demonstrated unlike that
realized with a catalyst comprised of each component alone. This is thought to be a
unique effect demonstrated as a result of compounding a nickel compound and X that
is the result of a novel catalyst action completely different from that demonstrated by
each component alone due to a dual functional effect between both metal
components or the formation of a new active species. On the basis of this novel
concept, in the case of supporting oxidized nickel and X on a support in a highly
dispersed state, astonishing catalyst performance unable to be obtained with

conventional catalysts was able to be realized.
[0026]
For example, if gold is selected for X and nickel oxide and gold are supported
onto a support in a highly dispersed state, remarkably high catalyst performance
appears. This catalyst was observed to demonstrate a high degree of carboxylic
acid ester selectivity and a considerable improvement in activity at a specific
composite ratio of Ni/Au as compared with respectively supporting nickel oxide or gold
alone onto a support. The catalyst also demonstrates high catalytic activity per metal
atom as compared with support particles comprised of each component alone, and
the appearance of catalyst performance as a result of their compounding is strongly
dependent on the supported composition of nickel and gold. This is presumed to be
due to the presence of an optimum ratio for the formation of a nickel oxidation state
that is optimum for the reaction. In this manner, highly prominent compounding
effects, which cannot be predicted from the simple combined addition of each
component alone, are demonstrated as a result of dispersing two components
comprising the nickel oxide and gold and supporting onto a support.
[0027]
The supported composite particle material in which gold is selected for X have
the oxidized nickel and gold supported onto a support in a highly dispersed state, and
both components have been observed to be compounded at the nanometer level.
Based on the results of transmission electron microscope/scanning transmission
electron microscope (TEM/STEM) observations, nearly spherical nanoparticles
measuring 2 to 3 nm are uniformly dispersed and supported on a support. According
to an elementary analysis of the nanoparticles by energy dispersive X-ray
spectrometry (EDS), all of the particles were observed to contain nickel and gold, and
the nickel was observed to be coating the surface of gold nanoparticles. In addition,

a nickel component alone was also observed to be supported onto the support in
addition to the nanoparticles containing nickel and gold.
[0028]
According to the results of X-ray photoelectron spectroscopy (XPS) and powder
X-ray diffraction (XRD), although gold is present in the form of a crystalline metal,
nickel is presumed to be present in the form of an amorphous oxide having a
bivalence.
[0029]
On the basis of ultraviolet-visible spectroscopy (UV-Vis), a surface plasmon
absorption peak (at about 530 nm) originating from gold nanoparticles observed in
gold nanoparticles of a single metal species was determined to disappear when nickel
oxide and gold were compounded. The phenomenon involving disappearance of
this surface plasmon absorption peak was not observed in catalysts comprised of
combinations of gold and metal oxide species other than nickel oxide not observed to
have an effect on the reaction (including metal oxides such as chromium oxide,
manganese oxide, iron oxide, cobalt oxide, copper oxide or zinc oxide). The
disappearance of this surface plasmon absorption peak is thought to be the result of
the formation of a mixed electron state mediated by the contact interface between
oxidized nickel and gold, or in other words, the result of hybridization of two types of
metallic chemical species.
[0030]
Conversion to highly oxidized nickel oxide can be confirmed by a color change
of a catalyst and ultraviolet-visible spectroscopy (UV-Vis). As a result of adding gold
to nickel oxide, the nickel oxide changed in color from grayish green to brown, and the
UV spectrum demonstrated absorbance over nearly the entire visible light region.
The shape of the UV spectrum and the color of the catalyst were similar to that of
highly oxidized nickel oxide (NiO2) measured as a reference sample. On the basis of

this finding, nickel is presumed to be converted to a highly oxidized nickel oxide by the
addition of gold.
[0031]
On the basis of the above results, the structure of the composite particles in the
case of selecting gold for X is believed to be such that the gold particles serve as the
core and the surface thereof is coated with highly oxidized nickel oxide, without any
gold atoms present on the surface of the composite particles.
[0032]
The supported composition of nickel and X onto a support is preferably within a
range of from 0.20 to 0.99, more preferably within a range of from 0.30 to 0.90, and
even more preferably within a range of from 0.50 to 0.90, in terms of the atomic ratio
of Ni/(Ni + X). The term "atomic ratio of Ni/(Ni + X)" used herein refers to a ratio of
the number of atoms of nickel supported onto the support to the total number of atoms
of nickel and X.
[0033]
The composite particles are preferably supported onto the support in a highly
dispersed state. The composite particles are more preferably supported by being
dispersed in the form of microparticles or a thin film, and the mean particle diameter
thereof is preferably from 2 to 10 nm, more preferably from 2 to 8 nm, and even more
preferably from 2 to 6 nm.
If the mean particle diameter of the composite particles is within the above
ranges, a specific active species structure comprised of nickel and X is formed and
reaction activity tends to improve. Here, mean particle diameter in the present
embodiment refers to the number average particle diameter as measured with a
transmission electron microscope (TEM). More specifically, in an image observed
with a transmission electron microscope, area of black contrast indicate composite
particles, and the mean particle diameter thereof can be calculated by measuring the

diameter of each particle for all particles.
[0034]
The composition of nickel and X in the composite particles is preferably within a
range of from 0.1 to 10, more preferably within a range of from 0.2 to 5.0 and even
more preferably within a range of from 0.3 to 3.0 in terms of the atomic ratio of Ni/X.
If the atomic ratio of Ni/X is within the above ranges, a specific active species
structure comprised of nickel and X and a nickel oxidized state optimum for the
reaction are formed, and as a result thereof, activity and selectivity tend to be higher
than a supported composite particle material comprised of nickel and X outside the
above ranges.
[0035]
Although there are no particular limitations on the form of the composite
particles provided both of the components of nickel and X are contained therein,
preferably both components are present in the particles, and the particles are in a
form having a phase structure, such as a solid solution structure in which chemical
species randomly occupy crystal sites, a core-shell structure in which each chemical
species is separated in the shape of concentric spheres, a anisotropic phase
separation structure in which phases are separated anisotropically, or a
heterobondphilic structure in which both chemical species are present adjacent to
each other on the particle surface. More preferably, the composite particles have a
form in which they have a core comprised of X and oxidized nickel is coated onto the
surface of the cores. There are no particular limitations on the shape of the
composite particles provided both components are contained therein, and the shape
may be spherical or hemispherical and the like.
[0036]
As previously described, transmission electron microscopy/scanning
transmission electron microscopy (TEM/STEM), for example, is effective as an

analysis technique for observing the form of the composite particles, and elementary
analyses within the particles and extraction of images of the distribution of elements
therein are possible by irradiating nanoparticles observed by TEM/STEM with an
electron beam. The composite particles of the present embodiment contain nickel
and X in all of the particles thereof as will be indicated in the examples to be described
later, and have been confirmed to have a form in which the surface of X is coated with
nickel. In the case of having such a form, the atomic ratio of nickel and X varies
according to the locations of the composition analysis points in the particles, and
nickel is detected in larger amounts on the edges of the particles than in the central
portion thereof. Thus, there are variations in the atomic ratio of nickel and X
depending on the locations of the analysis points even among individual particles, and
the range thereof is included in the range of the atomic ratio of Ni/X as previously
described.
[0037]
In the case of having selected gold, silver or copper for X, ultraviolet-visible
spectroscopy (UV-Vis) is an effective means of identifying the structure thereof. In
the case of nanoparticles of gold, silver or copper alone, coupling occurs between the
photoelectric field of the visible to near infrared region and free electrons on the
surface of the metal resulting in the occurrence of surface plasmon absorption. For
example, when a catalyst supported with gold particles is irradiated with visible light,
an absorption spectrum is observed that is based on plasmon resonance originating
from gold particles at a wavelength of about 530 nm. However, in the supported
composite particle material in which nickel oxide and gold are supported according to
the present embodiment, since the surface plasmon absorption thereof disappears,
gold can be considered to not be present on the surface of the composite particles of
the present embodiment.

[0038]
There are no particular limitations on the solid form of the nickel provided the
prescribed activity is obtained, and is preferably in an amorphous form in which
diffraction peaks are not observed in X-ray diffraction. As a result of having such a
form, in the case of using as a catalyst of an oxidation reaction, interaction with
oxygen is presumed to increase, and since the bonding interface between the
oxidized nickel and X increases, even better activity tends to be obtained.
[0039]
In the present embodiment, X is at least one of elements selected from the
group consisting of nickel, palladium, platinum, ruthenium, gold, silver and copper,
and is more preferably selected from the group consisting of nickel, palladium,
ruthenium, gold and silver.
[0040]
Although the chemical state of X may be a metal, an oxide, an hydroxide, a
composite oxide containing X and nickel or one or more types of another metal
element, or a mixture thereof, the chemical state of X is preferably a metal or oxide,
and more preferably a metal. In addition, there are no particular limitations on the
solid form of X provided the prescribed activity is obtained, the form may be either a
crystalline form or an amorphous form.
[0041]
The term "another metal element" used herein refers to a constituent element of
a support to be described later, a third component other than oxidized nickel and X
contained in the supported composite particle material, or a metal component such as
an alkaline metal, alkaline earth metal or rare earth metal.
[0042]
The supported composite particle material according to the present embodiment
has oxidized nickel and X supported onto a support as previously described, and

demonstrates superior effects as a result of forming composite particles comprised of
oxidized nickel and X. Furthermore, the term "composite particle" used herein refers
to a particle containing different binary metal species in a single particle. Examples
of different binary metal species may include binary metal particles in which both the
nickel and X are metals and metal particles forming an alloy or intermetallic compound
of nickel and X, and the case of using these as catalysts for chemical synthesis, the
selectivity of the target product and the activity of the catalyst tend to be lower than the
supported composite particle material according to the present embodiment.
[0043]
The supported composite particle material according to the present embodiment
preferably contains oxidized nickel alone on the support in addition to the composite
particles comprised of oxidized nickel and X. The presence of oxidized nickel not
compound with X further enhances the structural stability of the supported particles,
and inhibits increases in pore diameter caused by prolonged reactions as well as the
accompanying growth of the composite particles. This effect is particularly
remarkable in the case of using an aluminum-containing silica-based composition
containing silica and alumina for the support as will be described later.
[0044]
The following provides an explanation of mechanism that enhances structural
stability of the supported composite particle material and that inhibits increases in
pore diameter caused by prolonged reactions as well as the accompanying growth of
composite particles by having oxidized nickel alone present on a support.
[0045]
As will be described later, in a synthesis reaction of a carboxylic acid ester, by
adding a compound of an alkaline metal or alkaline earth metal to the reaction system
to maintain a pH of the reaction system at 6 to 9, and more preferably to neutral
conditions (for example, pH 6.5 to 7.5), namely as close to pH 7 as possible, it is

possible to inhibit the production of acetals and other by-products caused by acidic
substances exemplified by methacrylic acid or acrylic acid that are unique by-products
of carboxylic acid ester production reactions.
[0046]
According to studies conducted by the present inventors, in the case of carrying
out a prolonged reaction according to the reaction procedure described above using a
supported gold particle material in which single-component gold particles are
supported onto a support comprised of an aluminum-containing silica-based
composition containing silica and alumina, structural changes were determined to
occur, although gradually, in the supported gold particle material. This phenomenon
is thought to be caused by an increase in pore diameter of the supported particle
material due to the supported particle material being locally and repeatedly exposed
to acid and base causing a portion of the Al in the support to dissolve and precipitate
and resulting in rearrangement of the silica-alumina crosslinked structure. In
addition, accompanying changes causing an increase in pore diameter, sintering of
the gold particles occurs, and this was determined to lead to a decrease in catalyst
activity due to a decrease in surface area.
[0047]
On the other hand, the presence of composite particles and oxidized nickel
alone on the support enhanced the structural stability of the supported particle
material according to the reaction procedure described above, thereby inhibiting
increases in pore diameter and growth of the composite particles. As was previously
described, the formation of nickel oxide compounds or composite oxides containing
nickel in the form of a solid solution and the like as result of oxidized nickel reacting
with constituent elements of the support is considered to be factor behind the reason
for this, and as a result of such nickel compounds acting to stabilize the silica-alumina

crosslinked structure, structural changes in the supported particle material are thought
to have greatly improved. The present inventors presumed that the appearance of
this support structure stabilizing effect is attributable to the oxidized nickel present in
the support. Consequently, although this effect is naturally obtained in the case
oxidized nickel contained in composite particles is in contact with the support, even
greater stabilizing effects are thought to be obtained in the case oxidized nickel is
present alone on the support.
[0048]
There are no particular limitations on the support of the supported composite
particle material according to the present embodiment provided oxidized nickel and X
can be supported onto the support, and conventional catalyst supports used for
chemical synthesis can be used.
[0049]
Examples of supports may include various types of supports such as activated
charcoal, silica, alumina, silica-alumina, titania, silica-titania, zirconia, magnesia,
silica-magnesia, silica-alumina-magnesia, calcium carbonate, zinc oxide, zeolite,
crystalline metallosilicate or the like. Preferable examples of supports may include
activated charcoal, silica, alumina, silica-alumina, silica-magnesia,
silica-alumina-magnesia, titania, silica-titania and zirconia. More preferable
examples may include silica-alumina and silica-alumina-magnesia.
[0050]
In addition, one or a plurality of types of metal components selected from the
group consisting of alkaline metals (Li, Na, K, Rb or Cs), alkaline earth metals (Be, Mg,
Ca, Sr or Ba) and rare earth metals (La, Ce or Pr) may be contained in the support.
Metal components that become oxides as a result of firing, such as nitrates or
acetates, are preferably used for the metal components supported onto the support.
[0051]

A support comprised of an aluminum-containing silica-based composition
containing silica and aluminum is preferably used for the support. The support has
higher water resistance than silica and higher acid resistance than alumina. In
addition, the support is provided with properties superior to supports typically used in
the prior art, including greater hardness and higher mechanical strength than
activated charcoal, and is also able to stably support the active components in the
form of oxidized nickel and X. As a result, the reactivity of the supported composite
particle material can be maintained over a long period of time.
[0052]
The supported composite particle material having a specific atomic ratio for
oxidized nickel and X and using an aluminum-containing silica-based composition for
the support has high mechanical strength, is physically stable and satisfies corrosion
resistance with respect to liquid properties unique to the reaction despite having a
large surface area suitable for use as a catalyst support in the case of using as a
catalyst for chemical synthesis.
[0053]
The following provides an explanation of the characteristics of a support
comprised of an alumina-containing silica-based composition containing silica and
alumina of the present embodiment capable of considerably improving catalyst life.
Reasons for being able to greatly improve the mechanical strength and chemical
stability of the support are as described below.
[0054]
The support comprised of an aluminum-containing silica-based composition
contains newly formed Si-O-AI-O-Si bonds resulting from the addition of aluminum
(Al) to a non-crosslinked silica (Si-O) chain of a silica gel, and as a result of an
Al-crosslinked structure having been formed without any loss of the inherent stability
to acidic substances of the Si-0 chain, it is thought that the Si-O bonds are

strengthened, thereby resulting in a considerable improvement in the stability of
hydrolysis resistance (to be simply referred to as "water resistance"). In addition,
when a Si-O-AI-O-Si crosslinked structure is formed, the number of non-crosslinked
Si-0 chains decreases in comparison with the case of silica gel alone, and this is
thought to increase mechanical strength. Namely, there is presumed to be a
correlation between the number of Si-O-AI-O-Si structures formed and improvement
of the mechanical strength and water resistance of the resulting silica gel.
[0055]
One of the reasons for it being possible to stably support the oxidized nickel and
X on a support for a long period of time is that the mechanical strength and chemical
stability of the support are greatly improved as previously described, enabling it to be
provided with superior physical properties in comparison with typically used supports
of the prior art. As a result, it is difficult for the active components in the form of
nickel and X to separate from the support, which is thought to enable the nickel and X
to be stably supported over a long period of time.
[0056]
In the case of typically used supports such as silica or silica-titania, nickel
components are observed to elute from the support, although gradually, in prolonged
reactions. In contrast, in the case of using the support described above, the present
inventors found that elution of nickel components is suppressed over a long period of
time. On the basis of the results of X-ray photoelectron spectroscopy (XPS),
transmission electron microscopy (TEM/EDX) and high-resolution X-ray fluorescence
(HRXRF), in the case of using a silica or silica-titania support, eluted nickel
components were confirmed to be nickel oxide present alone on the support. Since
nickel oxide is a soluble compound in acid, in the case of using as a catalyst for
carboxylic acid ester synthesis, it is presumed to be eluted by acidic substances

exemplified by methacrylic acid or acrylic acid that are unique by-products of the
reaction.
[0057]
On the basis of analyses of the chemical state of nickel by high-resolution X-ray
fluorescence (HRXRF), the nickel in the supported composite particle material
according to the present embodiment is presumed to not contain a single compound
in the form of nickel oxide alone, but rather form composite oxides containing nickel
such oxidized compounds of nickel formed as a result of bonding between nickel
oxide and constituent component elements of the support, or a solid solution or
mixture thereof.
[0058]
High-resolution X-ray fluorescence (HRXRF) has extremely high energy
resolution and is able to analyze chemical state from the energy levels (chemical
shifts) and shapes of the resulting spectrum. In the Ka spectra of 3d transition metal
elements in particular, changes appear in chemical shift and shape due to changes in
valence or electronic state, thereby making it possible analyze the chemical state in
detail. In the supported composite particle material according to the present
embodiment, changes appear in the Ni Ka spectrum, and a chemical state was
confirmed for nickel that differs from that of a single compound in the form of nickel
oxide.
[0059]
For example, nickel aluminate, which is formed from nickel oxide and alumina, is
a compound that is insoluble in acid. As a result of forming such a nickel compound
on a support, elution of nickel components is presumed to be greatly improved.
[0060]
In a preferable elementary composition of the support comprised of an
aluminum-containing silica-based composition containing silica and alumina, the

amount of aluminum is from 1 to 30 mol%, preferably from 5 to 30 mol% and more
preferably from 5 to 25 mol% based on the total molar amount of silicon and aluminum.
If the amount of aluminum is within the above ranges, acid resistance and mechanical
strength tend to be satisfactory.
[0061]
In addition, the support in the supported composite particle material according to
the present embodiment preferably further contains an oxide of at least one of basic
metals selected from the group consisting of alkaline metals, alkaline earth metals and
rare earth metals, in addition to silica and alumina, from the viewpoint of further
improving mechanical strength and chemical stability. Examples of alkaline metals of
the basic metal components may include Li, Na, K, Rb and Cs, examples of alkaline
earth metals may include Be, Mg, Ca, Sr and Ba, while examples of rare earth metals
may include La, Ce and Pr.
[0062]
In the elementary composition of the support containing silica, alumina and at
least one of basic metals selected from the group consisting of alkaline metals,
alkaline earth metals and rare earth metals, the amount of aluminum is from 1 to 30
mol%, preferably from 5 to 30 mol% and more preferably from 5 to 25 mol% based on
the total molar amount of silicon and aluminum. In addition, the compositional ratio
of basic metal oxide to alumina, in terms of the atomic ratio of (alkaline metal + 1/2 x
alkaline earth metal + 1/3 x rare earth metal) / Al, is preferably within a range of from
0.5 to 10, more preferably within a range of from 0.5 to 5.0 and even more preferably
within a range of from 0.5 to 2.0. If the elementary composition of silica, alumina and
basic metal oxide is within the above ranges, the silicon, aluminum and basic metal
oxide form a specific stable bonding structure, and as a result thereof, the mechanical
strength and water resistance of the support tend to be satisfactory.
[0063]

The following provides an explanation of a preferable method for preparing a
support having a composition as described above.
There are no particular limitations on the method for preparing a support
comprised of an aluminum-containing silica-based composition containing silica and
alumina, and an aluminum-containing silica-based composition obtained according to
any of (1) to (5) below can be prepared by firing under conditions to be described later.
(1) Use of a commercially available silica-alumina compound solution
(2) Reacting a silica sol with an aluminum compound solution
(3) Reacting a silica sol with an aluminum compound insoluble in water
(4) Reacting a silica gel with an aqueous solution of a water-soluble aluminum
compound
(5) Reacting a silica gel and an aluminum compound in a solid phase reaction
[0064]
The following provides a detailed explanation of the support preparation
methods referred to in (2) to (5) above.
In the methods of (2) to (5) above, a silica sol or silica gel is used for the silica
source. The silica gel is that having non-crosslinked Si sites that react with Al, and
there are no particular restrictions on the length of the Si-0 chain. Although
water-soluble compounds such as sodium aluminate, aluminum chloride hexahydrate,
aluminum perchlorate hexahydrate, aluminum sulfate, aluminum nitrate nonahydrate
or aluminum diacetate are preferable for the aluminum compound, compounds that
are insoluble in water, such as aluminum hydroxide or aluminum oxide, can also be
used provided they are compounds that react with non-crosslinked Si in the silica sol
and silica gel.
[0065]
In the case of the methods of (2) and (3) that use a silica sol as a starting

material, after obtaining a mixed sol containing silica sol and an aluminum compound
by mixing the silica sol and an aluminum compound, the mixed sol is subjected to a
hydrothermal reaction at 20 to 100°C for 1 to 48 hours and dried to obtain a gel
followed by firing under temperature, time and atmospheric conditions to be described
later. Alternatively, an alkaline aqueous solution is added to the above-mentioned
mixed sol followed by co-precipitating silica and an aluminum compound, drying and
firing under conditions to be described later. In addition, a support comprised of an
aluminum-containing silica-based composition having a desired particle diameter can
be obtained by either pulverizing the above-mentioned mixed sol directly using a
spray dryer or by a step in which the mixed sol is dried following by granulating the
gel.
[0066]
In the case of the method of (3) in particular, although a silica sol is reacted with
an aluminum compound insoluble in water, at this time the aluminum compound can
be pulverized in advance to a prescribed particle diameter or can be preliminarily
coarsely pulverized. After mixing and reacting the silica sol and the water-insoluble
aluminum compound and drying, the mixture is further fired under conditions to be
described later. The fired silica-alumina compound may also be pulverized to a
prescribed particle diameter without pre-pulverizing the aluminum compound.
[0067]
In the case of the method of (4) using a silica gel for the starting material, an
aqueous solution of a water-soluble aluminum compound is reacted with the silica gel,
and the silica gel may be pulverized to a prescribed particle diameter in advance, or
may be preliminarily coarsely pulverized. After mixing and reacting the silica gel with
the water-soluble aluminum compound at 20 to 100°C for 1 to 48 hours, the mixture is
dried and further fired for 1 to 48 hours under conditions to be described later. The

fired silica-alumina compound may also be pulverized to a prescribed particle
diameter without preliminarily pulverizing the silica gel.
[0068]
The method of (5), which similarly uses a silica gel for the starting material,
involves the preparation of an aluminum-containing silica composition by reacting the
silica gel with an aluminum compound in a solid phase reaction. The Al is reacted in
a solid phase state with non-crosslinked Si. The silica gel and the aluminum
compound may be pulverized to a prescribed particle diameter in advance. In
addition, they may also be preliminarily coarsely pulverized. Pulverization may be
carried out for each substance alone or may be carried out after mixing both
substances. Firing is carried out under temperature, time and atmospheric
conditions to be described later. After the reaction, the resulting
aluminum-containing silica composition can also be used after pulverizing to a
prescribed particle diameter following the reaction without preliminarily pulverizing the
silica gel and aluminum compound.
[0069]
In a method for preparing a support containing silica, alumina and an oxide of at
least one of basic metals selected from the group consisting of alkaline metals,
alkaline earth metals and rare earth metals, the support can be prepared by drying a
slurry obtained by mixing an alkaline metal oxide, alkaline earth metal oxide and/or
rare earth metal oxide into silica and aluminum components and then firing under
conditions to be described later in accordance with the above-mentioned method for
preparing a support comprised of an aluminum-containing silica-based composition
containing silica and alumina.
[0070]
Atypical commercially available compound can be used as a raw material of the
alkaline metal, alkaline earth metal or rare earth metal in the same manner as the

aluminum raw materials. The raw material is preferably a water-soluble compound
and more preferably a hydroxide, carbonate, nitrate or acetate.
[0071]
In another preparation method that can be used, a basic metal component
selected from the group consisting of alkaline metals, alkaline earth metals and rare
earth metals is adsorbed onto a support comprised of an aluminum-containing
silica-based composition. For example, a method using an immersion method in
which a support is added to a liquid in which is dissolved a basic metal compound
followed by drying treatment, or a method using an impregnation method in which a
basic metal compound equivalent to pore volume is worked into a support followed by
drying treatment, can be applied. However, a method in which the basic metal
component is adsorbed later requires caution in that liquid drying treatment must be
carried out under mild conditions after having highly dispersed the basic metal
component in the support.
[0072]
In addition, inorganic substances or organic substances can be added to the
mixed slurry of each of the raw materials described above in order to control slurry
properties and finely adjust the pore structure or other characteristics of the product or
the properties of the resulting support.
[0073]
Specific examples of inorganic substances used may include inorganic acids
such as nitric acid, hydrochloric acid or sulfuric acid, salts of metals such as alkaline
metals such as Li, Na, K, Rb or Cs or alkaline earth metals such as Mg, Ca, Sr or Ba,
water-soluble compounds such as ammonia or ammonium nitrate, and clay minerals
that form a suspension by being dispersed in water. In addition, specific examples of
organic substances may include polymers such as polyethylene glycol, methyl
cellulose, polyvinyl alcohol, polyacrylic acid, polyacrylamide or the like.

[0074]
Although there are various effects of adding inorganic substances or organic
substances, the main effects include the formation of a spherical support and
controlling pore diameter and pore volume. More specifically, the liquid properties of
the mixed slurry are an important factor in obtaining a spherical support. Adjusting
viscosity and solid content using an inorganic substance or inorganic substance
makes it possible to alter the liquid properties to facilitate the obtaining of a spherical
support. In addition, pore diameter and pore volume can be controlled by selecting
the optimum organic compound that remains inside the support at the molding stage
after which residual substances are able to be removed during firing after molding and
by washing.
[0075]
The support can be produced by spray-drying the mixed slurry of each raw
material and additive described above. A known spraying device of, for example, a
rotating disk type, two-fluid nozzle type or pressurized nozzle type can be used as the
method for converting the mixed slurry into liquid droplets.
[0076]
The liquid to be sprayed is required to be used in a well-mixed state. If the
liquid is not properly mixed, it affects the performance of the support, such as
decreased durability caused by uneven distribution of components. When
formulating the raw materials in particular, increases in slurry viscosity or partial
gelling (colloidal condensation) may occur, resulting in the risk of the formation of
non-uniform particles. Consequently, in addition to taking into consideration
gradually mixing the raw materials while stirring, for example, controlling a pH to a
semi-stable region of the silica sol such as around pH 2 may be preferable by using a
method such as adding acid or alkali.
[0077]

The liquid to be sprayed is also required to have a certain degree of viscosity
and solid content. If viscosity and solid content are excessively low, the porous body
obtained by spray-drying may not form a perfect sphere and instead may form
numerous indentations therein. In addition, if viscosity and solid content are
excessively high, in addition to having a detrimental effect on the dispersibility of
porous bodies, stable droplets are unable to be formed depending on the properties
thereof. Consequently, the viscosity is preferably within a range of from 5 to 10,000
cps provided the liquid is able to be sprayed, and in terms of shape, higher viscosities
tend to be preferable provided the liquid is able to be sprayed, while in consideration
of the balance with ease of manipulation, the viscosity is selected to be within a range
of from 10 to 1,000 cps. In addition, a solid content within a range of from 10 to 50%
by mass is preferable in terms of shape and particle diameter. Furthermore, as a
general reference for spray-drying conditions, the hot air temperature at the entrance
to the drying tower of the spray dryer is preferably within a range of from 200 to 280°C,
and the drying tower outlet temperature is preferably within a range of from 110 to
140°C.
[0078]
The support firing temperature is typically selected to be within a range of from
200 to 800°C. If the support is fired at a temperature above 800°C, specific surface
area tends to decrease considerably, thereby making this undesirable. In addition,
although there are no particular limitations on the firing atmosphere, firing is typically
carried out in air or nitrogen. In addition, although the firing time can be determined
according to the specific surface area after firing, it is generally from 1 to 48 hours.
Since firing conditions cause changes in the porosity and other properties of the
support, it is necessary to select suitable temperature conditions and heating
conditions. If the firing temperature is too low, it tends to be difficult to maintain

durability as a composite oxide, while if the firing temperature is too high, there is the
risk of causing a decrease in pore volume. In addition, heating conditions are
preferably such that the temperature rises gradually by using a heating program and
the like. In the case of firing under extremely high temperature conditions,
gasification and combustion of inorganic substances and organic substances
becomes violent, thereby exposing the support to a high-temperature state beyond
that which has been set and causing the support to be pulverized.
[0079]
From the viewpoints of ease of supporting composite particles, reaction activity
in the case of using as a catalyst, resistance to separation and reaction activity, the
specific surface area of the support is preferably 10 m2/g or more, more preferably 20
m2/g or more, and even more preferably 50 m2/g or more as measured by BET
nitrogen adsorption. Although there are no particular limitations on specific surface
area from the viewpoint of activity, from the viewpoints of mechanical strength and
durability, the specific surface area is preferably 700 m2/g or less, more preferably 350
m2/g or less and even more preferably 300 m2/g or less.
[0080]
The pore structure of the support is an extremely important property in terms of
long-term stability, including supporting characteristics of metal components other
than strength, as well as reaction characteristics. Pore diameter is a physical
property value required to demonstrate these characteristics. If pore diameter is
smaller than 3 nm, although the separation properties of the supported metal tend to
be satisfactory, in the case of using as a catalyst in a liquid phase reaction and the like,
pore diameter is preferably 3 nm or more from the viewpoint of not making the
intrapore diffusion resistance excessively great so that the diffusion process of the
reaction substrate is not rate-limiting as well as maintaining reaction activity at a high

level. On the other hand, the pore diameter is preferably 50 nm or less from the
viewpoints of resistance to cracking of the supported material and resistance to
separation of the supported metal. Thus, the pore diameter of the support is
preferably from 3 to 50 nm, and more preferably from 3 to 30 nm. Pore volume is
required for the presence of pores capable of supporting compounded nanoparticles.
However, if pore volume is excessively large, a tendency is observed for strength to
suddenly decrease. Thus, from the viewpoints of strength and supporting
characteristics, pore volume is preferably within a range of from 0.1 to 1.0 mL/g and
more preferably within a range of from 0.1 to 0.5 mL/g. The support of the present
embodiment preferably satisfies the above ranges for both pore diameter and pore
volume.
[0081]
The shape of the support is selected according to the reaction form, selecting a
hollow cylindrical support or honeycomb structure resulting in little pressure loss in the
case of a fixed bed reaction, while under conditions of a liquid phase slurry
suspension, a spherical shape is generally selected after selecting the optimum
particle diameter in consideration of reactivity and the separation method. For
example, in the case of employing a generally simple catalyst separation process
based on precipitation separation, a particle diameter of from 10 to 20 µm is preferably
selected, that of from 20 to 150 µm is more preferably selected and that of from 30 to
150 µm is even more preferably selected based on the balance with reaction
characteristics. In the case of a cross filter reaction, small particles of 0.1 to 20 µm or
less are preferable since they yield higher reactivity. The supported composite
particle material can thus be used as a catalyst for chemical synthesis by changing
the type and form of the support according to the purpose of use.
[0082]

Although there are no particular limitations on the loading of oxidized nickel on
the support, the loading of oxidized nickel is generally from 0.01 to 20% by mass,
preferably from 0.1 to 10% by mass, more preferably from 0.2 to 5% by mass and
even more preferably 0.5 to 2% by mass as nickel based on the weight of the support.
The loading of X supported onto the support is generally from 0.01 to 10% by mass,
preferably from 0.1 to 5% by mass, more preferably from 0.2 to 2% by mass, even
more preferably from 0.3 to 1.5% by mass and particularly preferably from 0.5 to 1.0%
by mass as metal based on the weight of the support.
[0083]
Moreover, in the present embodiment, a preferable range exists for the atomic
ratio between nickel and the above-mentioned constituent elements of the support.
In the case of using the support comprised of an aluminum-containing silica-based
composition containing silica and alumina in the present embodiment, the
compositional ratio of nickel and alumina in a catalyst in terms of the atomic ration of
Ni/AI is preferably from 0.01 to 1.0, more preferably from 0.02 to 0.8 and even more
preferably from 0.04 to 0.6. In addition, in the case of using a support containing
silica, alumina and an oxide of at least one of basic metals selected from the group
consisting of alkaline metals, alkaline earth metals and rare earth metals, the atomic
ratio of nickel and alumina in the supported material in terms of the atomic ratio of
Ni/AI is preferably from 0.01 to 1.0, more preferably from 0.02 to 0.8 and even more
preferably from 0.04 to 0.6, and the compositional ratio of nickel and alkaline metal
component in terms of the atomic ratio of Ni/(alkaline metal + alkaline earth metal +
rare earth metal) is preferably from 0.01 to 1.2, more preferably from 0.02 to 1.0 and
even more preferably from 0.04 to 0.6.
[0084]
If the atomic ratios of nickel to support constituent elements in the form of

aluminum and basic metal oxide are within the above ranges, the effects of improving
nickel elution and structural changes in supported particle materials tend to increase.
This is thought to be because the nickel, aluminum and basic metal oxide form a
specific composite oxide within the above ranges, thereby forming a stable bonding
structure.
[0085]
The supported composite particle material according to the present embodiment
can also contain a third constituent element in addition to the active components in the
form of oxidized nickel and X. Examples of third constituent elements that can be
contained may include titanium, vanadium, chromium, manganese, lead, cobalt, zinc,
gallium, zirconium, niobium, molybdenum, rhodium, cadmium, indium, tin, antimony,
tellurium, hafnium, tantalum, tungsten, rhenium, osmium, iridium, mercury, thallium,
lead, bismuth, aluminum, boron, silicon and phosphorous. The content of these third
constituent elements is preferably from 0.01 to 20% by mass and more preferably
from 0.05 to 10% by mass in the supported material. In addition, at least one of
metal component selected from the group consisting of alkaline metals, alkaline earth
metals and rare earth metals may also be contained in the supported composite
particle material. The content of alkaline metal, alkaline earth metal or rare earth
metal is preferably selected to be within a range of 15% by mass or less in the
supported material.
[0086]
Furthermore, these third constituent elements or alkaline metal, alkaline earth
metal or rare earth metal may be contained in the supported composite particle
material during production or reaction of the supported composite particle material, or
a method may be used in which they are contained in the support in advance.
[0087]
The specific surface area of the supported composite particle material according

to the present embodiment is preferably within a range of from 20 to 350 m2/g, more
preferably from 50 to 300 m2/g and even more preferably from 100 to 250 m2/g as
measured by BET nitrogen adsorption from the viewpoints of reaction activity and
resistance to separation of active components.
[0088]
The pore structure of the supported composite particle material is an extremely
important property in terms of long-term stability, including supporting characteristics
and separation of metal components, as well as reaction characteristics, and pore
diameter is a physical property value required to demonstrate these characteristics.
If pore diameter is smaller than 3 nm, although the separation properties of the
supported metal component tend to be satisfactory, in the case of using as a catalyst
in a liquid phase reaction and the like, pore diameter is preferably 3 nm or more from
the viewpoint of not making the intrapore diffusion resistance excessively great so that
the diffusion process of the reaction substrate is not rate-limiting as well as
maintaining reaction activity at a high level. On the other hand, the pore diameter is
preferably 50 nm or less from the viewpoints of resistance to cracking of the supported
material and resistance to separation of the supported composite particles. Thus,
the pore diameter of the supported composite particle material is preferably from 3 to
50 nm, more preferably from 3 to 30 nm and even more preferably from 3 to 10 nm.
From the viewpoints of supporting characteristics and reaction characteristics, pore
volume is preferably within a range of from 0.1 to 1.0 mL/g, more preferably within a
range of from 0.1 to 0.5 mL/g and even more preferably within a range of from 0.1 to
0.3 mL/g. The supported composite particle material according to the present
embodiment preferably satisfies the above ranges for both pore diameter and pore
volume.
[0089]

[Process For Producing Supported Composite Particle Material]
There are no particular limitations on the method used to prepare the supported
composite particle material according to the present embodiment provided a
supported material as described above is obtained. The following provides an
explanation of a typical process for preparing the supported composite particle
material according to the present embodiment.
[0090]
In a first step, an aqueous slurry containing a support supported with an oxide of
at least one of basic metals selected from the group consisting of alkaline metals,
alkaline earth metals and rare earth metals is mixed with an acidic aqueous solution of
a soluble metal salt containing nickel and X (wherein X represents at least one of
elements selected from the group consisting of nickel, palladium, platinum, ruthenium,
gold, silver and copper). The temperature of the mixture of both liquids is adjusted
so that the temperature thereof is 60°C and above. A precursor of a supported
composite particle material in which nickel and the X component have precipitated is
formed on the support in the mixture.
[0091]
Next, in a second step, the precursor obtained in the first step is rinsed with
water and dried as necessary followed by subjecting to heat treatment to obtain the
supported composite particle material according to the present embodiment.
[0092]
According to this process, a supported composite particle material can be
obtained that has a supported layer in which the composite particles are localized but
does not contain composite particles in a region that includes the center of the
support.
[0093]
Prior to the first step, the support supported with an oxide of at least one of basic

metals selected from the group consisting of alkaline metals, alkaline earth metals and
rare earth metals is preferably aged in water. Aging the support in advance allows
the obtaining of a layer having a sharp distribution of composite particles. Based on
the results of measuring pore distribution by nitrogen adsorption, the effect produced
by aging the support is presumed to be the result of a more uniform and sharper pore
structure due to the occurrence of realignment of the support pore structure.
Although support aging can be carried out at room temperature, due to the slow rate
of changes in the pore structure thereof, a temperature higher than room temperature
is preferably selected within a range of from 60 to 150°C. In the case of aging at
normal pressure, a temperature within a range of from 60 to 100°C is preferable. In
addition, although the duration of aging treatment varies according to the temperature
conditions, it is preferably from 1 minute to 5 hours, more preferably from 1 to 60
minutes and even more preferably from 1 to 30 minutes at a temperature of 90°C, for
example. In the procedure of the first step, although the support can be used after
initially drying and then firing after it has been aged, a slurry in which the support is
dispersed in water is preferably contacted with the acidic aqueous solution of a
soluble metal salt containing nickel and X followed by insoluble fixation of the nickel
and X on the support.
[0094]
Examples of soluble metal salts containing nickel used to prepare a catalyst may
include nickel nitrate, nickel acetate, nickel chloride or the like. In addition, examples
of soluble metal salts containing X may include palladium chloride, palladium acetate
or the like in the case of selecting palladium for X, ruthenium chloride, ruthenium
nitrate or the like in the case of selecting ruthenium for X, chloroauric acid, sodium
tetrachloroaurate, potassium dicyanoaurate, gold diethylamine trichloride, gold
cyanide or the like in the case of selecting gold for X, and silver chloride, silver nitrate

or the like in the case of selecting silver for X.
[0095]
The respective concentrations of aqueous solutions containing nickel and X are
generally within a range of from 0.0001 to 1.0 mol/L, preferably from 0.001 to 0.5
mol/L and more preferably from 0.005 to 0.2 mol/L. The ratio of nickel and X in the
aqueous solutions in terms of the atomic ratio of Ni/X is preferably within a range of
from 0.1 to 10, preferably from 0.2 to 5.0 and more preferably from 0.5 to 3.0.
[0096]
The temperature during contact between the nickel and acidic aqueous solution
of a soluble metal salt containing nickel and X is one important factor for controlling
the distribution of composite particles, and although varying according to the amount
of oxide of at least one of basic metals selected from the group consisting of alkaline
metals, alkaline earth metals and rare earth metals supported in advance onto the
support, if the temperature is excessively low, the reaction slows and the distribution
of composite particles tends to widen. In the production process according to the
present embodiment, the temperature during contact with the acidic aqueous solution
of a soluble metal salt containing nickel and X, from the viewpoint of obtaining a
supported layer in which the composite particles are more sharply localized, is a
temperature at which the supported composite particle material is obtained at a high
reaction rate, and is preferably 60°C or higher, more preferably 70°C or higher, even
more preferably 80°C or higher and particularly preferably 90°C or higher. Since the
acidic aqueous solution and aqueous slurry are mixed so that the temperature of the
mixed liquid thereof is 60°C or higher, the aqueous slurry may be heated to a degree
such that the mixed liquid exceeds 60°C even after the acidic aqueous solution is
added, or conversely only the acidic aqueous solution may be heated. Both the
acidic aqueous solution and the aqueous slurry may naturally also be heated to 60°C

or higher.
[0097]
Although the reaction can be carried out under an applied pressure at a
temperature equal to or higher than the boiling point of the solvent, based on the ease
of the procedure, it is generally preferably carried out at a temperature equal to or
lower than the solvent boiling point. There are no particular limitations on the
duration of fixation of the nickel and X components, and although varying according to
conditions such as the type of support, the loading of nickel and X and the ratio
thereof, the duration is generally within a range of from 1 minute to 5 hours, preferably
from 5 minutes to 3 hours and more preferably from 5 minutes to 1 hour.
[0098]
The production process of the supported composite particle material according
to the present embodiment is based on the principle of insoluble fixation of the nickel
and X components by carrying out a chemical reaction between an oxide of at least
one of basic metals selected from the group consisting of alkaline metals, alkaline
earth metals and rare earth metals supported in advance on the support, and a
soluble metal salt containing nickel and X. These components are preferably fixed
simultaneously from a mixed solution containing both components in order to ensure
more adequate compounding of the nickel and X.
[0099]
In addition, in the production process according to the present embodiment, the
aqueous slurry containing a support supported with an oxide of at least one of basic
metals selected from the group consisting of alkaline metals, alkaline earth metals and
rare earth metals preferably contains a salt of at least one of basic metals selected
from the group consisting of alkaline metals, alkaline earth metals and rare earth
metals.
[0100]

As a result, the formation of metal black of X is inhibited, compounding of nickel
and X is promoted, and the distribution of composite particles can be controlled more
precisely. Such effects are presumed to be caused by controlling the rate of the
chemical reaction between the basic metal oxide supported in advance on the support
and the soluble metal salt containing nickel and X as a result of adding to the aqueous
solution a salt of at least one of metals selected from the group consisting of alkaline
metals, alkaline earth metals and rare earth metals.
[0101]
Examples of salts of at least one of basic metals selected from the group
consisting of alkaline metals, alkaline earth metals and rare earth metals that can be
used may include one or more types selected from water-soluble salts of these metals
such as organic acid salts, nitrates, chlorides or the like.
[0102]
The amount of the salt of at least one of basic metals selected from the group
consisting of alkaline metals, alkaline earth metals and rare earth metals as described
above varies according to the amounts and ratio of the nickel and X components, and
is determined according to the amount of basic metal oxide supported in advance
onto the support. Generally, the amount of the above salt is from 0.001 to 2 times
moles and preferably from 0.005 to 1 times moles based on the amount of nickel and
X components in the aqueous solution.
[0103]
In addition, the aqueous slurry containing a support supported with an oxide of
at least one of basic metals selected from the group consisting of alkaline metals,
alkaline earth metals and rare earth metals preferably contains a soluble aluminum
salt. Examples of soluble aluminum salts that can be used may include aluminum
chloride and aluminum nitrate.
[0104]

The addition of a soluble aluminum salt to the aqueous slurry allows the
formation of an outer layer substantially free of composite particles on the outside of
the supported layer in which composite particles are localized. This is also based on
the principle of insoluble fixation as previously described. Aluminum chloride or
aluminum nitrate and the like is used for the soluble aluminum salt, aluminum is
reacted on the outer surface of the support by a chemical reaction with the basic metal
oxide supported in advance onto the support, the nickel and X are consumed thereby,
and the outer layer is fixed by a reaction between the basic metal oxide inside and the
nickel and X.
[0105]
The amount of aluminum component varies according to how many µm the
thickness of the layer not supported with nickel or X component is set to, and is
determined according to the amount of basic metal oxide supported in advance onto
the support. Generally, the amount of aluminum component is from 0.001 to 2 times
moles and preferably from 0.005 to 1 times moles based on the amount of basic metal
oxide supported in advance onto the support.
[0106]
Although there are many aspects of the details of the mechanism by which the
nickel and X components are distributed that are unclear, it is presumed that the
balance with the rate at which the components are insolubilized by a chemical
reaction was effectively attained under the conditions of the present embodiment,
thereby making it possible to fix the composite particles in a narrow region near the
surface of the support.
[0107]
In addition, in the case of forming the outer layer substantially free of composite
particles on the outer surface of the support, since aluminum and a basic metal
component near the outer surface of the support are allowed to react resulting in

consumption of basic metal components capable of reacting with nickel and X
components near the outer surface of the support, and when nickel and X are
subsequently supported, the reactive basic metal components near the outer surface
of the support are already consumed, the nickel and X are presumed to be fixed as a
result of reacting with a basic metal compound inside the support.
[0108]
The following provides an explanation of the second step.
The precursor of the supported composite particle material is rinsed with water
and dried as necessary prior to the heat treatment of the second step. The
temperature at which the precursor is heated is generally from 40 to 900°C, preferably
from 80 to 800°C, more preferably from 200 to 700°C and even more preferably from
300 to 600°C.
[0109]
Heat treatment is carried out in an atmosphere such as air (or atmospheric air),
an oxidizing atmosphere (such as oxygen, ozone, nitrogen oxides, carbon dioxide,
hydrogen peroxide, hypochlorous acid or inorganic or organic peroxides), or an inert
gas atmosphere (such as helium, argon or nitrogen). The heating time is suitably
selected according to the heating temperature and amount of precursor. In addition,
heat treatment can be carried out at normal pressure, under applied pressure or under
reduced pressure.
[0110]
Following the second step as described above, reduction treatment can be
carried out in a reducing atmosphere (such as hydrogen, hydrazine, formalin or formic
acid) as necessary. In this case, a treatment method is selected that prevents the
oxidized nickel from being completely reduced to a metallic state. The temperature
and duration of reducing treatment are suitably determined according to the type of
reducing agent, type of X and amount of catalyst.

[0111]
Moreover, oxidizing treatment can be carried out following the above-mentioned
heat treatment and reducing treatment in air (or atmospheric air) or an oxidizing
atmosphere (such as oxygen, ozone, nitrogen oxides, carbon dioxide, hydrogen
peroxide, hypochlorous acid or inorganic or organic peroxides) as necessary. The
temperature and duration in this case is suitably determined according to the type of
oxidizing agent, type of X and amount of catalyst.
[0112]
A third constituent element other than nickel and X can be added during
production of the supported material or under reaction conditions. The alkaline metal,
alkaline earth metal or rare earth metal can also be added during catalyst preparation
or to the reaction system. In addition, the raw materials of the third constituent
element, alkaline metal, alkaline earth metal and rare earth metal are selected from
salts of organic acids, salts of inorganic acids, hydroxides and the like.
[0113]
As has been described above, according to the supported composite particle
material production process according to the present embodiment, the supported
composite particle material can be obtained having the supported layer in which
composite particles are localized comprised of oxidized nickel and X in specific
shallow region near the outer surface of the support, and as necessary, having a layer
substantially free of the composite particles on the outer surface of the support.
[0114]
[Process for Producing Compounds Using the Supported Composite Particle Material
as a Catalyst for Chemical Synthesis]
The supported composite particle material according to the present embodiment
can be widely used as a catalyst for chemical synthesis. For example, it can be used
as a catalyst or photocatalyst of reactions such as reactions for forming carboxylic

acid esters from aldehydes and alcohols, reactions for forming carboxylic acid esters
from alcohols, alkane oxidation reactions, alcohol oxidation reactions, aldehyde
oxidation reactions, olefin oxidation reactions, olefin epoxidation reactions, olefin
oxidative addition reactions, amine oxidation reactions, olefin hydrogenation reactions,
a,p-unsaturated ketone hydrogenation reactions, reactions for forming hydrogen
peroxide from hydrogen and oxygen, carbon monoxide oxidation reactions and NOx
reduction.
[0115]
The supported composite particle material according to the present embodiment
demonstrates superior effects particularly in the case of using as a catalyst of an
oxidation reaction. In addition to the aldehydes and alcohols used in the reaction for
forming carboxylic acid ester as indicated in the examples, other examples of reaction
substrates used in the present embodiment may include various reaction substrates
such as alkanes, olefins, alcohols, ketones, aldehydes, ethers, aromatic compounds,
phenols, sulfur compounds, phosphorous compounds, oxygen-containing nitrogen
compounds, amines, carbon monoxide and water. These reaction substrates can be
used alone, or two or more types can be used as a mixture. Various industrially
useful oxygen-containing compounds, oxidative addition products, oxidative
dehydrogenation products and other oxidation products are obtained from these
reaction substrates.
[0116]
Specific examples of reaction substrates in the form of alkanes may include
aliphatic alkanes such as methane, ethane, propane, n-butane, isobutane, n-pentane,
n-hexane, 2-methylpentane or 3-methylpentane, and alicyclic alkanes such as
cyclopentane, cyclohexane, cycloheptane or cyclooctane.
[0117]
Examples of olefins may include aliphatic olefins such as ethylene, propylene,

butene, pentene, hexene, heptene, octene, decene, 3-methyl-1-butene,
2,3-dimethyl-1-butene or allyl chloride, alicyclic olefins such as cyclopentene,
cyclohexene, cycloheptene, cyclooctene or cyclodecene, and aromatic substituted
olefins such as styrene or a-methylstyrene.
[0118]
Examples of alcohols may include saturated and unsaturated aliphatic alcohols
such as methanol, ethanol, n-propanol, isopropanol, n-butanol, s-butanol, t-butanol,
n-pentanol, n-hexanol, n-heptanol, allyl alcohol or crotyl alcohol, saturated and
unsaturated alicyclic alcohols such as cyclopentanol, cyclohexanol, cycloheptanol,
methylcyclohexanol or cyclohexen-1-ol, aliphatic and alicyclic polyvalent alcohols
such as ethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol,
1,2-cyclohexanediol or 1,4-cyclohexanediol, and aromatic alcohols such as benzyl
alcohol, salicyl alcohol or benzhydrol.
[0119]
Examples of aldehydes may include aliphatic saturated aldehydes such as
formaldehyde, acetoaldehyde, propionaldehyde, isobutylaldehyde or glyoxal, aliphatic
α,β-unsaturated aldehydes such as acrolein, methacrolein or crotonaldehyde,
aromatic aldehydes such as benzaldehyde, tolylaldehyde, benzylaldehyde or
phthalaldehyde, and derivatives of these aldehydes.
[0120]
Examples of ketones may include aliphatic ketones such as acetone, methyl
ethyl ketone, diethyl ketone, dipropyl ketone or methyl propyl ketone, alicyclic ketones
such as cyclopentanone, cyclohexanone, cyclooctanone, 2-methylcyclohexanone or
2-ethylcyclohexanone, and aromatic ketones such as acetophenone, propiophenone
and benzophenone.
[0121]
Examples of aromatic compounds may include benzene, toluene, xylene,

naphthalene, anthracene and derivatives thereof substituted with, for example, alkyl
groups, aryl groups, halogens or sulfone groups.
[0122]
Examples of phenols may include phenol, cresol, xylenol, naphthol, anthrol
(hydroxyanthracene) and derivatives thereof (such as those in which aromatic
hydrogen atoms are substituted with alkyl groups, aryl groups, halogen atoms or
sulfone groups).
[0123]
Examples of sulfur compounds may include mercaptans such as methyl
mercaptan, ethyl mercaptan, propyl mercaptan, benzyl mercaptan or thiophenol.
[0124]
Examples of amines may include aliphatic amines such as methylamine,
ethylamine, propylamine, isopropylamine, butylamine, dimethylamine, diethylamine,
dipropylamine, diisopropylamine, dibutylamine, trimethylamine, triethylamine,
tripropylamine, tributylamine, allylamine or diallylamine, alicyclic amines such as
cyclopentylamine, cyclohexylamine, cycloheptylamine or cyclooctylamine, and
aromatic amines such as aniline, benzylamine or toluidine.
[0125]
These reaction substrates can be used alone, or two or more types can be used
as a mixture. In addition, these reaction substrates are not necessarily required to
be purified, and may be in the form of mixtures with other organic compounds.
[0126]
The following provides an explanation of an example of a process for producing
carboxylic acid ester from aldehyde and alcohol in the presence of oxygen by an
oxidative esterification reaction using the supported composite particle material
according to the present embodiment as a catalyst.
[0127]
Examples of the aldehyde used as a raw material may include C1 to C10 aliphatic

aldehydes such as formaldehyde, acetoaldehyde, propionaldehyde, isobutylaldehyde,
glyoxal or the like; C2 to C10 alicyclic α-β unsaturated aldehydes such as acrolein,
methacrolein, crotonaldehyde or the like; C6 to C20 aromatic aldehydes such as
benzaldehyde, tolylaldehyde, benzylaldehyde, phthalaldehyde or the like; and
derivatives of these aldehydes. These aldehyde can be used alone, or any two or
more types can be used as a mixture.
[0128]
Examples of alcohols may include C1 to C10 aliphatic saturated alcohols such as
methanol, ethanol, isopropanol, butanol, 2-ethylhexanol, octanol or the like; C5 to C10
alicyclic alcohols such as cyclopentanol, cyclohexanol or the like; C2 to C10 diols such
as ethylene glycol, propylene glycol, butanediol or the like; C3 to C10 aliphatic
unsaturated alcohols such as allyl alcohol, methallyl alcohol or the like; C6 to C20
aromatic alcohols such as benzyl alcohol or the like; and hydroxyoxetanes such as
3-alkyl-3-hydroxymethyloxetane or the like. These alcohols can be used alone, or
any two or more types can be used as a mixture.
[0129]
There are no particular limitations on the weight ratio of aldehyde to alcohol, and
although the reaction can be carried out over a wide range of molar ratios of
aldehyde/alcohol of from 10 to 1/1,000 the reaction is generally carried out within the
range of a molar ratio of from 1/2 to 1/50.
[0130]
The amount of catalyst used can be varied considerably according to, for
example, the types of reaction raw materials, composition and preparation method of
the catalyst, reaction conditions and reaction form, and although there are no
particular limitations thereon, in the case of reacting the catalyst in the form of a slurry,
the amount of catalyst in terms of the solid content in the slurry is preferably within the
range of from 1 to 50 wt/vol%, more preferably from 3 to 30 wt/vol% and even more

preferably from 10 to 25 wt/vol%.
[0131]
In the production of carboxylic acid ester, the reaction may be carried out either
in batches or continuously using an arbitrary method such as a vapor phase reaction,
liquid phase reaction or reflux reaction.
[0132]
Although the reaction can be carried out in the absence of solvent, it can also be
carried out using a solvent that is inert with respect to the reaction components such
as hexane, decane, benzene, dioxane or the like.
[0133]
A known form such as a fixed bed type, fluidized bed type or stirred tank type
can be used for the reaction form. For example, when carrying out the reaction in a
liquid phase, any type of reactor can be used, such as a bubble column reactor, draft
tube type reactor, stirred tank reactor or the like.
[0134]
The oxygen used to produce carboxylic acid ester can be molecular oxygen,
namely can be in the form of oxygen gas itself or a mixed gas in which the oxygen gas
has been diluted with a diluent that is inactive in the reaction such as nitrogen or
carbon dioxide gas, and air is preferably used for the oxygen raw material from the
viewpoints of ease of manipulation, economy and the like.
[0135]
Although oxygen partial pressure varies according to the reaction raw materials
such as the type of aldehyde or type of alcohol, the reaction conditions or the type of
reactor and the like, the oxygen partial pressure at the reactor outlet is, for practical
reasons, within the range equal to or lower than the lower limit of the explosive range,
and is preferably controlled to, for example, from 20 to 80 kPa. Although reaction
can be carried out at a reaction pressure extending over a wide pressure range from

depressurization to pressurization, the reaction is normally carried out at a pressure
within the range of from 0.05 to 2 MPa. In addition, it is preferable from the viewpoint
of safety to set the total pressure so that the oxygen concentration of the reactor
outflow gas does not exceed the explosive limit (for example, a concentration of 8%).
[0136]
In the case of carrying out a carboxylic acid ester production reaction in a liquid
phase, the pH of the reaction system is preferably maintained at from 6 to 9 by adding
a compound of an alkaline metal or alkaline earth metal (such as an oxide, hydroxide,
carbonate or carboxylate) to the reaction system. These alkaline metal or alkaline
earth metal compounds can be used alone, or two or more types can be used in
combination.
[0137]
Although the reaction temperature during production of carboxylic acid ester is
such that the reaction can be carried out at high temperatures above 200°C, the
reaction temperature is preferably from 30 to 200°C, more preferably from 40 to
150°C and even more preferably from 60 to 120°C. There are no particular
limitations on the reaction time, and although not determined unconditionally since it
varies according to the set conditions, it is generally from 1 to 20 hours.
[Examples]
[0138]
Although the following provides a more detailed explanation of the present
embodiment through examples and comparative examples thereof, the present
embodiment is not limited thereto. A person with ordinary skill in the art can not only
carry out the examples indicated below, but also make various changes thereto, and
such changes are also included within the scope of the claims for patent.
[0139]

Furthermore, in the examples and comparative examples, measurement of the
distributions of nickel and X in the supported composite particle material, observation
of the form of the support and supported composite particle material, measurement of
mean particle diameter, determination of the loading of Ni and X and atomic ratio of
Ni/(Ni + X), determination of the content of support constituent elements (Si, Al, basic
metal), analysis of the crystal structure of composite particles, analysis of the
chemical state of composite particle metal elements, analysis of the chemical state of
nickel, morphological observation and elementary analysis of composite particles,
measurement of the ultraviolet-visible spectra of composite particles and
measurement of the physical properties of the support and supported composite
particle material (specific surface area, pore diameter, pore volume) were carried out
according to the methods described below.
[0140]
[Measurement of Distributions of Nickel and X in Supported Composite Particle
Material]
A sample obtained by embedding the resulting supported composite particle
material in resin and polishing was measured at an acceleration voltage of 15 kV
using the Shimadzu Model 1600 X-ray Microprobe (EPMA). Ni and X (Au) in the
direction of depth from the outer surface were analyzed on the basis of electron
reflected images and X-ray analysis (Ni - wavelength: 14.5829, analyzing crystal:
RAP; X (Au) -wavelength: 5.8419, analyzing crystal: PET).
[0141]
[Morphological Observation of Support and Supported Composite Particle
Material]
The support and supported composite particle material were observed using the
Hitachi X-650 Scanning Electron Microscopy System (SEM).
[0142]

[Measurement of Mean Particle Diameter of Support and Supported Composite
Particle Material]
Mean particle diameter (volume-based) was measured using the
Beckman-Coulter Model LS230 Laser Diffraction/Scattering Particle Size Distribution
Measuring System.
[0143]
[Determination of Loading of Ni and X and Atomic Ratio of Ni/(Ni+X)]
The concentrations of Nickel and X in the supported composite particle material
were quantified using the Thermo Fisher Scientific Model IRIS Intrepid III XDL ICP
Emission Spectrometer (ICP-AES, MS).
Samples were prepared by weighing out a supported material into a Teflon
decomposition vessel, adding nitric acid and hydrogen fluoride and heating and
decomposing with the Milestone General Model ETHOS-TC Microwave
Decomposition System, followed by evaporating to dryness over a heater, adding
nitric acid and hydrochloric acid to the precipitated residue, heating under an applied
pressure with a microwave decomposition system, and using a fixed amount of the
resulting pure decomposition product as a test liquid.
The quantification method was carried out by quantifying with ICP-AES with an
internal standard and then determining the contents of nickel and X in the catalyst by
subtracting a simultaneously determined blank value followed by calculating the
loading and atomic ratio.
[0144]
[Determination of Contents of Support Constituent Elements (Si, Al,
Basic Metal]
Samples were prepared by dissolving the support with aqua regia and dissolving
with molten alkali salt. The content of basic metal and/or Mg was measured for the

sample dissolved with aqua regia and the contents of Al and Si were measured for the
sample dissolved with molten alkali salt using the Seiko Instruments Model JY-38P2
ICP Emission Spectrometer (ICP-AES) followed by calculation of the atomic ratios
from the resulting metal contents.
[0145]
[Analysis of Crystal Structure of Composite Particles]
Crystal structure was analyzed using the Rigaku Model Rint 2500 Power X-Ray
Diffraction System (XRD) under conditions of a Cu tube for the X-ray source (40 kV,
200 mA), measuring range of 5 to 65 degrees (0.02 deg/step), measuring speed of
0.2 deg/min and slit widths (scattering, divergence, reception) of 1 deg, 1 deg and
0.15 mm.
The sample was prepared by uniformly spraying onto a non-reflective sample
plate and fixing with neoprene rubber.
[0146]
[Analysis of Chemical State of Composite Particle Metal Components]
The chemical state of composite particle metal components was analyzed using
the Thermo Electron Model ESCALAB 250 X-Ray Photoelectron Spectroscopy
System (XPS) under conditions of Al Ka at 15 kV x 10 mA for the excitation source,
analyzed surface area of about 1 mm (shape: oval), using a 0 to 1,100 eV survey scan
and an Ni2p narrow scan for the uptake region.
The measurement samples were prepared by crushing the supported composite
particle material with an agate mortar and pestle and placing on a special-purpose
powder sample stage followed by XPS measurement.
[0147]
[Analysis of Chemical State of Nickel]
Ni Ka spectra were measured with the Technos Model XFRA190
High-Resolution X-Ray Fluorescence Spectroscopy System (HRXRF), and each of

the resulting parameters was compared with those of standard substances (nickel
metal, nickel oxide) to predict the chemical state such as valence of nickel present in
the supported material.
The measurement samples were used directly for measurement. The Ka
spectrum of Ni was measured in the partial spectral mode. At that time, Ge (220)
was used for the analyzing crystal, a slit having a vertical divergence angle of 1
degree was used for the slit, and the excitation voltage and current were set to 35 kV
and 80 mA, respectively. Filter paper was then used for the absorber in the case of
the reference sample, counting time was selected for each sample in the case of
supported material samples, and measurements were carried out so that the peak
intensity of the Ka spectra was 3,000 cps or less and 10,000 counts or more.
Measurement was repeated five times for each sample, and metal samples were
measured before and after each repeated measurement. After subjecting measured
spectra to smoothing processing (S-G method, 7 points, 5 times), the peak locations,
half-width values (FWHM) and asymmetry indices (Al) were calculated, and peak
locations were treated as a chemical shift (AE) from the measured value of the metal
sample measured before and after measurement of each sample.
[0148]
[Morphological Observation and Elementary Analysis of Composite Particles]
TEM bright field images, STEM dark field images and STEM-EDS compositional
analyses (point analyses, mapping, line analyses) were measured using the JEOL
Model 3100FEF transmission electron microscope/scanning transmission electron
microscope (TEM/STEM) (acceleration voltage: 300 kV, with energy dispersive X-ray
detector (EDX)).
The data analysis software contained Digital Micrograph™ Ver. 1.70.16 from
Gatan for TEM image and STEM image analyses (length measurement, Fourier

transform analysis), and the NORAN System SIX Ver. 2.0 from Thermo Fisher
Scientific for EDS data analyses (mapping image processing, compositional
quantification and calculation).
The measurement samples were prepared by crushing the supported composite
particle material with a mortar and pestle followed by dispersing in ethanol. After
subjecting to ultrasonic cleaning for about 1 minute, the powder was dropped onto a
molybdenum microgrid and air-dried to obtain TEM/STEM observation samples.
[0149]
[Measurement of Ultraviolet-Visible Spectra of Composite Particles]
UV and visible spectra were measured using the Jasco Model V-550
Ultraviolet-Visible Spectrophotometer (UV-Vis) (with integrating sphere unit and
powder sample holder) at a measuring range of 800 to 200 nm and scanning speed of
400 nm/min.
The measurement samples were prepared by crushing the supported composite
particle material with an agate mortar and pestle and placing in the powder sample
holder for measurement of UV-Vis spectra.
[0150]
[Measurement of Physical Properties of Support and Supported Composite
Particle Material: Specific Surface Area, Pore Diameter, Pore Volume]
Physical properties were measured with the Yuasa Ionics 3MP AutoSorb
System using nitrogen gas for the adsorbing gas (nitrogen adsorption method). The
BET method was used for specific surface area, the BJH method for pore diameter
and pore distribution, and the amount of adsorption at maximum P/Po was used for
pore volume.
[0151]
[Support Production Reference Example]
An aqueous solution in which 3.75 kg of aluminum nitrate nonahydrate, 2.56 kg

of magnesium nitrate and 540 g of 60% nitric acid were dissolved in 5.0 L of pure
water was gradually dropped into 20.0 kg of a silica sol solution having a colloidal
particle diameter of 10 to 20 nm while stirring and holding at 15°C (Nissan Chemical
Industries, Snowdex N-30, Si02 content: 30% by mass) to obtain a mixed slurry of
silica sol, aluminum nitrate and magnesium nitrate. Subsequently, the mixed slurry
was aged by holding at 50°C for 24 hours. After cooling to room temperature, the
mixed slurry was spray-dried with a spray dryer set to an outlet temperature of 130°C
to obtain a solid.
Next, the resulting solid was filled to a thickness of about 1 cm into a stainless
steel container having an open top followed by heating an electric furnace from room
temperature to 300°C over the course of 2 hours and holding at that temperature for 3
hours. Moreover, after heating to 600°C over the course of 2 hours and holding at
that temperature for 3 hours, the solid was cooled to obtain a support. The resulting
support contained 83.3 mol%, 8.3 mol% and 8.3 mol% of silicon, aluminum and
magnesium, respectively, based on the total molar amount of silicon, aluminum and
magnesium. The specific surface area as determined by nitrogen adsorption was
149 m2/g, the pore volume was 0.27 mL/g and the mean pore diameter was 8 nm.
The mean particle diameter of the support was 60 µm based on the results of
measurement of laser diffraction/scattering particle size distribution. In addition, the
form of the support was determined to be nearly spherical based on observations
using a scanning electron microscope (SEM).
[0152]
[Example 1]
300 g of the support obtained in the Support Production Reference Example
were dispersed in 1.0 L of water heated to 90°C followed by stirring for 15 minutes at
90°C. Next, an aqueous solution containing 16.35 g of nickel nitrate hexahydrate

and 12 mL of a 1.3 mol/L aqueous solution of chloroauric acid was prepared followed
by heating to 90°C, adding the above-mentioned support slurry and continuing to stir
for 30 minutes at 90°C to insolubly fix the nickel and gold component on the support.
Next, after removing the supernatant by allowing to stand undisturbed and
washing several times with distilled water, the washed supernatant was filtered.
After drying for 10 hours at 105°C with a dryer, the product was fired for 5 hours at
450°C in air in a muffle furnace to obtain a supported composite particle material
(NiOAu/SiO2-AI2O3-MgO) supported with 1.05% by mass of nickel and 0.91 % by mass
of gold. The atomic ratio of Ni/(Ni + Au) of the supported material thus obtained was
0.80.
A sample obtained by embedding the resulting supported composite particle
material in resin and polishing was subjected to X-ray analysis of a particle
cross-section using an X-ray microprobe (EPMA). The results are shown in FIG. 1.
As can be clear from FIG. 1, the supported composite particle material had an outer
layer substantially free of nickel and gold in a region at a depth of 0.5 µm from the
outermost surface of the support, nickel and gold were supported in a region
extending to a depth of 10 µm from the surface, and composite particles were
confirmed not be present within the support.
Next, when the form of the above-mentioned supported composite particle
material was observed with a transmission electron microscope (TEM/STEM),
spherical nanoparticles extensively distributed within a particle diameter of 2 to 3 nm
(number average particle diameter: 3.0 nm) was confirmed to be supported on the
support. Observation of the nanoparticles under higher magnification revealed
lattice fringe corresponding to the interplanar spacing of Au (111) in the nanoparticles.
Compositional point analysis of individual nanoparticles by STEM-EDS indicated that
nickel and gold were detected in all of the particles. The mean value of the atomic

ratio of nickel/gold of the nanoparticles (calculated quantity: 50) was 1.05. Moreover,
analysis of the nanoregions of the observed particles revealed the Ni/Au atomic ratio
in the central portions of the particles to be 0.90, while that on the edges of the
particles was 2.56. Trace amounts of nickel only were detected in portions other
than the particles. As a result of carrying out fifty similar measurements, nickel was
detected in large amounts in the edges of all particles. The distribution of nickel and
gold was observed to be nearly consistent based on the results of EDS elementary
mapping. In addition, the magnitude of the distribution of nickel was found to be one
level greater than that of the distribution of gold in all scanning direction based on the
results of compositional line profiles.
Based on the results of powder X-ray diffraction (XRD), a diffraction pattern
attributable to nickel was not observed, and nickel was confirmed to be present in an
amorphous state. On the other hand, although not well-defined, a broad peak was
present corresponding to gold crystals. Although the value is close to the detection
limit of powder X-ray diffraction (2 nm), the mean crystallite diameter thereof was
about 3 nm as calculated according to the Scherrer equation. With respect to the
chemical state of nickel, nickel was confirmed to be bivalent based on the results of
X-ray photoelectron spectroscopy (XPS).
The chemical state of nickel was also predicted to be such that the nickel was in
a high-spin state and have a valence of 2 based on the results of high-resolution X-ray
fluorescence (HRXRF), and was determined to have a different chemical state than a
single compound in the form of nickel oxide due to differences in the Ni Kα spectra.
The half-width value (FWHM) of the Ni Ka spectrum of the resulting catalyst based on
the measured spectrum was 3.470 and the chemical shift (AE) was 0.335. The
half-width value (FHWM) of the Ni Kα spectrum of nickel oxide measured as a
reference substance was 3.249 while the chemical shift (AE) was 0.344.

In addition, as a result of investigating changes in electron excitation states of
the supported composite particle material by ultraviolet-visible spectroscopy (UV-Vis),
a surface plasmon absorption peak originating from gold nanoparticles did not appear
in the vicinity of 530 nm, while broad absorption attributable to NiO2 was observed in
the wavelength range of 200 to 800 nm.
On the basis of these results, the microstructure of the composite particles was
predicted to have a form in which the surfaces of gold nanoparticles are covered by
oxidized nickel.
[0153]
[Example 2]
1.0 L of an aqueous solution in which was dissolved 2.90 g of magnesium
chloride was heated to 80°C and stirred followed by the addition of 300 g of the
support obtained in the Support Production Reference Example and further stirring for
15 minutes at 80°C. Next, an aqueous solution containing 37.16 g of nickel nitrate
hexahydrate and 35 mL of a 2.0 mol/L aqueous solution of palladium chloride was
prepared followed by adding that heated to 80°C to the above-mentioned support
slurry and continuing to stir for 30 minutes at 80°C to insolubly fix the nickel and
palladium component on the support.
Next, after removing the supernatant by allowing to stand undisturbed and
washing several times with distilled water, the washed supernatant was filtered.
After drying for 10 hours at 105°C, the product was fired for 5 hours at 500°C in air.
Next, the supported material thus obtained was subjected to reducing treatment at
room temperature for 2 hours in a hydrogen atmosphere to obtain a supported
composite particle material (NiOPd/α-alumina) supported with 2.48% by mass of
nickel and 2.30% by mass of palladium. The atomic ratio of Ni/(Ni + Pd) of the
supported material thus obtained was 0.66.

A sample obtained by embedding the resulting supported composite particle
material in resin and polishing was subjected to X-ray analysis of a particle
cross-section using an X-ray microprobe (EPMA). The results are shown in FIG. 2.
As can be clear from FIG. 2, nickel and palladium were confirmed to be supported in a
region at a depth of 17 µm from the support surface while being absent inside.
Next, based on the results of powder X-ray diffraction (XRD) of the supported
composite particle material, a diffraction pattern attributable to nickel was not
observed, and nickel was confirmed to be present in an amorphous state. On the
other hand, although not well-defined, a broad peak was present corresponding to
palladium crystals. The mean crystallite diameter thereof was about 5 nm as
calculated according to the Scherrer equation. With respect to the chemical state of
Ni, nickel was confirmed to be bivalent based on the results of X-ray photoelectron
spectroscopy (XPS).
In addition, when the state of active species of this supported material was
observed with a transmission electron microscope (TEM/STEM), nanoparticles
extensively distributed within a particle diameter of 4 to 5 nm (number average particle
diameter: 4.8 nm) were confirmed to be supported on the support. Elementary
analyses (20 points) were then carried out on individual observed nanoparticles with
the energy dispersive X-ray detector (EDX) provided, and nickel and palladium were
confirmed to be contained in all particles. The atomic ratio of nickel/palladium (mean
value) of these composite particles was 0.8.
[0154]
[Example 3]
1.0 L of an aqueous solution in which was dissolved 3.66 g of aluminum nitrate
nonahydrate was heated to 80°C and stirred followed by the addition of 300 g of the
support obtained in the Support Production Reference Example and further stirring for

10 minutes at 80°C. Next, an aqueous solution containing 25.78 g of nickel nitrate
hexahydrate and 37 mL of a 1.3 mol/L aqueous solution of chloroauric acid was
prepared followed by adding that heated to 80°C to the above-mentioned support
slurry and continuing to stir for 15 minutes at 80°C to insolubly fix the nickel and gold
component on the support.
Next, after removing the supernatant by allowing to stand undisturbed and
washing several times with distilled water, the washed supernatant was filtered.
After drying for 10 hours at 105°C, the product was fired for 5 hours at 400°C in an air
to obtain a supported composite particle material (NiOAu/SiO2-Al2O3-MgO) supported
with 2.20% by mass of nickel and 1.96% by mass of gold. The atomic ratio of Ni/(Ni
+ Au) of the supported material thus obtained was 0.79.
A sample obtained by embedding the resulting supported composite particle
material in resin and polishing was subjected to X-ray analysis of a particle
cross-section using an X-ray microprobe (EPMA). As a result, the supported
composite particle material was confirmed to have an outer layer substantially free of
nickel and gold in a region extending to a depth of 2.0 µm from the outermost surface
of the support, and nickel and gold were supported in a region extending to a depth of
15 µm from the surface, while being absent inside.
Next, based on the results of powder X-ray diffraction (XRD) of the supported
composite particle material, a diffraction pattern attributable to nickel was not
observed, and nickel was confirmed to be present in an amorphous state. On the
other hand, although not well-defined, a broad peak was present corresponding to
gold crystals. The mean crystallite diameter thereof was about 4 nm as calculated
according to the Scherrer equation. With respect to the chemical state of Ni, nickel
was confirmed to be bivalent based on the results of X-ray photoelectron
spectroscopy (XPS).

In addition, when the state of active species of this supported material was
observed with a transmission electron microscope (TEM/STEM), nanoparticles
extensively distributed within a particle diameter of 3 to 4 nm (number average particle
diameter: 3.8 nm) were confirmed to be supported on the support. Elementary
analyses (20 points) were then carried out on individual observed nanoparticles with
the energy dispersive X-ray detector (EDX) provided, and nickel and gold were
confirmed to be contained in all particles. The atomic ratio of nickel/gold (mean
value) of these composite particles was 1.10.
[0155]
[Example 4]
A supported composite particle material (NiOAu/SiO2-AI2O3-MgO) supported
with 1.02% by mass of nickel and 0.89% by mass of gold was obtained by preparing in
the same manner as Example 1 with the exception of not aging the support and
stirring the support slurry and aqueous solution containing nickel and gold for 15
minutes at 60°C. The atomic ratio of Ni/(Ni + Au) of the supported material thus
obtained was 0.79.
A sample obtained by embedding the resulting supported composite particle
material in resin and polishing was subjected to X-ray analysis of a particle
cross-section using an X-ray microprobe (EPMA). As a result, nickel and gold were
confirmed to be supported in a region extending to a depth of 25 µm from the support
surface, while being absent inside.
Next, based on the results of powder X-ray diffraction (XRD) of the supported
composite particle material, a diffraction pattern attributable to nickel was not
observed, and nickel was confirmed to be present in an amorphous state. On the
other hand, although not well-defined, a broad peak was present corresponding to
gold crystals. The mean crystallite diameter thereof was about 3 nm as calculated

according to the Schemer equation. With respect to the chemical state of Ni, nickel
was confirmed to be bivalent based on the results of X-ray photoelectron
spectroscopy (XPS).
In addition, when the state of active species of this supported material was
observed with a transmission electron microscope (TEM/STEM), nanoparticles
extensively distributed within a particle diameter of 3 to 4 nm (number average particle
diameter: 3.5 nm) were confirmed to be supported on the support. Elementary
analyses (20 points) were then carried out on individual observed nanoparticles with
the energy dispersive X-ray detector (EDX) provided, and nickel and gold were
confirmed to be contained in all particles. The atomic ratio of nickel/gold (mean
value) of these composite particles was 1.02.
[0156]
[Example 5]
A commercially available silica (Fuji Silysia Chemical, Cariact Q-10, particle
diameter: 150 µm) was impregnated with 4% by mass of lanthanum followed by firing
in air for 5 hours at 600°C. Next, 1.0 L of an aqueous solution in which was dissolved
8.91 g of aluminum nitrate nonahydrate was heated to 70°C and stirred followed by
the addition of 300 g of the above-mentioned silica support and further stirring for 30
minutes at 70°C. Next, an aqueous solution containing 17.84 g of nickel nitrate
hexahydrate and 14 mL of a 1.3 mol/L aqueous solution of chloroauric acid was
prepared followed by the addition of that heated to 70°C to the support slurry and
further continuing to stir for 30 minutes at 70°C to insolubly fix the nickel and gold
component on the support.
Next, after removing the supernatant by allowing to stand undisturbed and
washing several times with distilled water, the washed supernatant was filtered.
After drying for 10 hours at 105°C, the product was fired for 3 hours at 550°C in air to

obtain a supported composite particle material (NiOAu/SiO2-La2O3) supported with
1.10% by mass of nickel and 1.02% by mass of gold. The atomic ratio of Ni/(Ni + Au)
of the supported material thus obtained was 0.78.
A sample obtained by embedding the resulting supported composite particle
material in resin and polishing was subjected to X-ray analysis of a particle
cross-section using an X-ray microprobe (EPMA). As a result, the supported
composite particle material was confirmed to have an outer layer substantially free of
nickel and gold in a region extending to a depth of 5.0 µm from the outermost surface
of the support, and nickel and gold were supported in a region extending to a depth of
30 µm from the surface, while being absent inside.
Next, based on the results of powder X-ray diffraction (XRD) of the supported
composite particle material, a diffraction pattern attributable to nickel was not
observed, and nickel was confirmed to be present in an amorphous state. On the
other hand, although not well-defined, a broad peak was present corresponding to
gold crystals. Although close to the detection limit of powder X-ray diffraction (2nm,
the mean crystallite diameter thereof was about 3 nm as calculated according to the
Scherrer equation. With respect to the chemical state of Ni, nickel was confirmed to
be bivalent based on the results of X-ray photoelectron spectroscopy (XPS).
In addition, when the state of active species of this supported material was
observed with a transmission electron microscope (TEM/STEM), nanoparticles
extensively distributed within a particle diameter of 2 to 3 nm (number average particle
diameter: 3.2 nm) were confirmed to be supported on the support. Elementary
analyses (20 points) were then carried out on individual observed nanoparticles with
the energy dispersive X-ray detector (EDX) provided, and nickel and gold were
confirmed to be contained in all particles. The atomic ratio of nickel/gold (mean
value) of these composite particles was 1.02.

[0157]
[Example 6]
A commercially available spherical alumina (Sumitomo Chemical, KHD, particle
diameter: 3 mm) was impregnated with 5% by mass of potassium followed by firing in
air for 5 hours at 600°C. Next, 300 g of the resulting alumina support was dispersed
in 1.0 L of water heated to 90°C and stirred for 15 minutes at 90°C. Next, an
aqueous solution containing 38.65 g of nickel nitrate hexahydrate and 30 ml_ of a 1.3
mol/L aqueous solution of chloroauric acid was prepared followed by the addition of
that heated to 90°C to the support slurry and further continuing to stir for 30 minutes at
90°C to insolubly fix the nickel and gold component on the support.
Next, after removing the supernatant by allowing to stand undisturbed and
washing several times with distilled water, the washed supernatant was filtered.
After drying for 10 hours at 105°C, the product was fired for 5 hours at 400°C in air to
obtain a supported composite particle material (NiOAu/Al2O3-K) supported with 2.50%
by mass of nickel and 2.46% by mass of gold. The atomic ratio of Ni/(Ni + Au) of the
supported material thus obtained was 0.77.
A sample obtained by embedding the resulting supported composite particle
material in resin and polishing was subjected to X-ray analysis of a particle
cross-section using an X-ray microprobe (EPMA), and measurement of the
distribution of nickel and gold was able to confirm that nickel and gold were supported
in a region extending to 50 µm from the surface of the support, while being absent
inside.
Next, based on the results of powder X-ray diffraction (XRD) of the supported
composite particle material, a diffraction pattern attributable to nickel was not
observed, and nickel was confirmed to be present in an amorphous state. On the
other hand, although not well-defined, a broad peak was present corresponding to

gold crystals. The mean crystallite diameter thereof was about 4 nm as calculated
according to the Scherrer equation. With respect to the chemical state of Ni, nickel
was confirmed to be bivalent based on the results of X-ray photoelectron
spectroscopy (XPS).
In addition, when the state of active species of this supported material was
observed with a transmission electron microscope (TEM/STEM), nanoparticles
extensively distributed within a particle diameter of 3 to 4 nm (number average particle
diameter: 3.6 nm) were confirmed to be supported on the support. Elementary
analyses (20 points) were then carried out on individual observed nanoparticles with
the energy dispersive X-ray detector (EDX) provided, and nickel and gold were
confirmed to be contained in all particles. The atomic ratio of nickel/gold (mean
value) of these composite particles was 0.94.
[0158]
[Comparative Example 1]
1.0 L of an aqueous solution containing 16.35 g of nickel nitrate hexahydrate
and 12 ml of a 1.3 mol/L aqueous solution of chloroauric acid was heated to 40°C. A
supported composite particle material (NiOAu/SiO2-AI2O3-MgO) supported with 1.07%
by mass of nickel and 0.90% by mass of gold was obtained by preparing using the
same procedure as Example 1 with the exception of adding 300 g of the support
obtained in the Support Production Reference Example to this aqueous solution,
continuing to stir for 30 minutes while holding at 40°C and insolubly fixing the nickel
and gold component on the support. The atomic ratio of Ni/(Ni + Au) of the
supported material thus obtained was 0.80.
A sample obtained by embedding the supported material thus obtained in resin
and polishing was subjected to X-ray analysis of a particle cross-section using an
X-ray microprobe (EPMA). The results are shown in FIG. 3. On the basis of FIG. 3,

nickel and gold can be seen to be supported by being uniformly distributed from the
surface to the interior.
Next, based on the results of powder X-ray diffraction (XRD) of the supported
composite particle material, a diffraction pattern attributable to nickel was not
observed, and nickel was confirmed to be present in an amorphous state. On the
other hand, although not well-defined, a broad peak was present corresponding to
gold crystals. Although close to the detection limit of powder X-ray diffraction (2 nm),
the mean crystallite diameter thereof was about 3 nm as calculated according to the
Scherrer equation. With respect to the chemical state of Ni, nickel was confirmed to
be bivalent based on the results of X-ray photoelectron spectroscopy (XPS).
In addition, when the state of active species of this supported material was
observed with a transmission electron microscope (TEM/STEM), nanoparticles
extensively distributed within a particle diameter of 2 to 3 nm (number average particle
diameter: 3.2 nm) were confirmed to be supported on the support. Elementary
analyses (20 points) were then carried out on individual observed nanoparticles with
the energy dispersive X-ray detector (EDX) provided, and nickel and gold were
confirmed to be contained in all particles. The atomic ratio of nickel/gold (mean
value) of these composite particles was 0.97.
[0159]
[Comparative Example 2]
A supported gold particle material (Au/SiO2-AI2O3-MgO) supported with 0.90%
by mass of gold was obtained by preparing a supported material using the same
procedure as Example 1 with the exception of not adding nickel nitrate hexahydrate.
A sample obtained by embedding the resulting supported gold particle material
in resin and polishing was subjected to X-ray analysis of a particle cross-section using
an X-ray microprobe (EPMA). The results are shown in FIG. 5. On the basis of FIG.

1
5, gold can be seen to be supported by being uniformly distributed from the surface to
the interior.
Next, based on the results of powder X-ray diffraction (XRD), a broad peak was
present corresponding to gold crystals. The mean crystallite diameter thereof was
about 3 nm as calculated according to the Scherrer equation. When the state of the
supported gold particle material was observed with a transmission electron
microscope (TEM), gold particles having a mean particle diameter of 2.9 nm were
confirmed to be supported on the support. In addition, as a result of investigating the
electron excitation state of this supported gold particle material by ultraviolet-visible
spectroscopy (UV-Vis), a surface plasmon absorption peak originating from gold
particles was observed (at about 530 nm).
Table 1 shows the physical properties of the supported composite particle
material of Examples 1 to 6 and Comparative Examples 1 and 2.
[0160]
Table 1




[Example 7]
240 g of the supported composite particle material of Example 1 were charged
into a stirred stainless steel reactor equipped with a catalyst separator and having a
liquid phase portion of 1.2 liters, followed by carrying out a oxidative carboxylic acid
ester formation reaction from aldehyde and alcohol while stirring the contents at a rate
in terms of the stirrer tip speed of 4 m/s. A 36.7% by masst methacrolein/methanol
solution at 0.6 liters/hr and a 1 to 4% by mass NaOH/methanol solution at 0.06
liters/hr were continuously supplied to the reactor, air was blown in at a reaction
temperature of 80°C and reaction pressure of 0.5 MPa so that the outlet oxygen
concentration was 4.0% by volume (equivalent to oxygen partial pressure of 0.02
MPa), and the concentration of NaOH supplied to the reactor was controlled so that a
pH of the reaction system was 7. The reaction product was continuously extracted
from the reactor outlet by overflow and reactivity was investigated by analyzing by gas
chromatography.
At 500 hours after the start of the reaction, the methacrolein conversion rate was
75.4%, the selection rate of methyl methacrylate was 97.2%, and the formation
activity of methyl methacrylate based on the supported material unit mass was 9.568
mol/h/kg-cat. Reactivity after 2000 hours had elapsed indicated a methacrolein
conversion rate of 75.1%, methyl methacrylate selection rate of 97.1% and methyl
methacrylate formation activity of 9.520 mol/h/kg-cat, thus showing hardly any change

in reactivity. When the supported composite particle material was recovered and the
loading of nickel and gold after 2000 hours were compared with the initial loading
thereof, the nickel and gold losses were 0.1% or less, respectively, thus confirming
that separation and elution of active components in the form of nickel and gold was
inhibited.
Next, when the recovered supported composite particle material was observed
with a transmission electron microscope (TEM/STEM), composite particles
extensively distributed within a particle diameter of 2 to 3 nm (number average particle
diameter: 3.2 nm) were confirmed to be supported on the support. Compositional
point analysis of individual composite particles by STEM-EDS confirmed that nickel
and gold were contained in all of the particles. The mean value of the atomic ratio of
nickel/gold of the composite particles (calculated quantity: 50) was 1.10. In addition,
as a result of investigating changes in electron excitation states of the supported
material by ultraviolet-visible spectroscopy (UV-Vis), a surface plasmon absorption
peak originating from gold particles was not observed in the vicinity of 530 nm.
[0162]
[Comparative Example 3]
A reaction was carried out under the same operating conditions as Example 1
using the supported composite particle material of Comparative Example 1. As a
result, at 500 hours after the start of the reaction, the methacrolein conversion rate
was 63.4%, the selection rate of methyl methacrylate was 95.8%, and the formation
activity of methyl methacrylate based on the supported material unit mass was 6.608
mol/h/kg-cat. Reactivity after 2000 hours had elapsed indicated a methacrolein
conversion rate of 58.7%, methyl methacrylate selection rate of 95.7% and methyl
methacrylate formation activity of 6.111 mol/h/kg-cat, thus showing decreases in
reaction activity and selectivity. When the supported composite particle material was

recovered and the loading of nickel and gold after 2000 hours were compared with the
initial loading thereof, the nickel and gold losses were 3.0% and 2.0%, respectively.
The number average particle diameter of the composite particles as determined with a
transmission electron microscope (TEM) was 3.8 nm, and sintering of composite
particles was observed.
[0163]
[Comparative Example 4]
A reaction was carried out under the same operating conditions as Example 1
using the supported composite particle material of Comparative Example 2. As a
result, at 200 hours after the start of the reaction, the methacrolein conversion rate
was 25.1%, the selection rate of methyl methacrylate was 81.5%, and the formation
activity of methyl methacrylate based on the supported material unit mass was 2.671
mol/h/kg-cat. Reactivity after 700 hours had elapsed indicated a methacrolein
conversion rate of 18.3%, methyl methacrylate selection rate of 79.1% and methyl
methacrylate formation activity of 1.89 mol/h/kg-cat, thus showing decreases in
reaction activity and selectivity. When the supported composite particle material was
recovered and the loading of gold after 700 hours were compared with the initial
loading thereof, the gold loss was 8.5%. The number average particle diameter of
gold particles as determined with a transmission electron microscope (TEM) was 4.8
nm, and sintering of gold particles was observed.
[0164]
On the basis of the above results, the supported composite particle material of
the present embodiment was confirmed to maintain an extremely high level of
reactivity for a long period of time and the structure of the composite particles thereof
were confirmed to not change before and after the reaction in the case of using as a
catalyst of a carboxylic acid ester formation reaction as previously described.

Moreover, as a result of being provided with an outer layer substantially free of the
composite particles, a supported composite particle material is obtained in which
nickel and gold component loss caused by friction and the like can be inhibited. As
observed in the previously described reaction examples, when composite particles
are supported near the surface of the support, reaction activity increases and metal
component loss decreases. Thus, in comparison with conventional supported
materials, considerable improvement in economy can be obtained not only in this
specific reaction, but also in general in a wider range of numerous other reactions.
[0165
The present application is based on a Japanese patent application filed with the
Japanese Patent Office on October 26, 2007 (Japanese Patent Application No. 2007-
279397), the content of which is incorporated herein by reference.
Industrial Applicability
[0166]
The supported composite particle material according to the present invention
has industrial applicability as a catalyst for chemical synthesis such as a carboxylic
acid ester formation reaction between an aldehyde and an alcohol.

We claim:
1. A supported composite particle material comprising:
a composite particle formed of an oxidized nickel and X (wherein X represents at
least one of elements selected from the group consisting of nickel, palladium, platinum,
ruthenium, gold, silver and copper); and
a support on which the composite particle is supported,
wherein the supported composite particle material comprises a supported layer
in which the composite particle is localized.
2. The supported composite particle material according to Claim 1, wherein the
supported layer in which the composite particle is localized is present in a region
extending from a surface of the supported composite particle material to 40% of an
equivalent diameter of the supported composite particle material.
3. The supported composite particle material according to Claim 1 or 2,
wherein the equivalent diameter of the supported composite particle material exceeds
200 µm, and the supported layer in which the composite particle is localized is present
in a region extending by 80 µm from an outer surface of the supported composite
particle material.
4. The supported composite particle material according to Claim 1 or 2,
wherein the equivalent diameter of the supported composite particle material is 200
µm or less, and the supported layer in which the composite particle is localized is
present in a region extending from the surface of the supported composite particle
material to 30% of the equivalent diameter of the supported composite particle

material.
5. The supported composite particle material according to any one of Claims
1 to 4, comprising an outer layer substantially free of the composite particle on an
outside of the supported layer in which the composite particle is localized.
6. The supported composite particle material according to Claim 5, wherein
the outer layer is formed at a thickness of 0.01 to 15 µm from the outer surface of the
support.
7. The supported composite particle material according to any one of Claims
1 to 6, wherein the composite particle has a mean particle diameter of from 2 to 10
nm.
8. The supported composite particle material according to any one of Claims
1 to 7, wherein a compositional ratio of nickel and X in the composite particle, in terms
of an atomic ratio of Ni/X, is from 0.1 to 10.
9. The supported composite particle material according to any one of Claims
1 to 8, wherein the composite particle has a core formed of X and the core is coated
with oxidized nickel.
10. The supported composite particle material according to any one of
Claims 1 to 9, wherein the support is formed of an aluminum-containing silica-based
composition containing silica and alumina.

11. A process for producing a supported composite particle material in which
the composite particle formed of an oxidized nickel and X (wherein X represents at
least one of elements selected from the group consisting of nickel, palladium, platinum,
ruthenium, gold, silver and copper) is supported onto a support, comprising:
a first step of obtaining a mixture at a temperature of at least 60°C by mixing an
aqueous slurry containing a support on which is supported an oxide of at least one of
basic metals selected from the group consisting of alkaline metals, alkaline earth
metals and rare earth metals, and an acidic aqueous solution of a soluble metal salt
containing nickel and the X; and
a second step of heat-treating a precursor contained in the mixture.
12. The process for producing the supported composite particle material
according to Claim 11, wherein the aqueous slurry further comprises a salt of at least
one of basic metals selected from the group consisting of alkaline metals, alkaline
earth metals and rare earth metals.
13. The process for producing the supported composite particle material
according to Claim 11 or 12, wherein the aqueous slurry further comprises a soluble
aluminum salt.
14. A process for producing carboxylic acid ester comprising:
reacting an aldehyde and an alcohol in the presence of oxygen by using the
supported composite particle material according to any one of Claims 1 to 10 as a
catalyst.
15. The process for producing carboxylic acid ester according to Claim 14,

A supported composite particle material comprises: a composite particle formed
of an oxidized nickel and X (wherein X represents at least one of elements selected
from the group consisting of nickel, palladium, platinum, ruthenium, gold, silver and
copper); and a support on which the composite particle is supported, the supported
composite particle material having a supported layer in which the composite particle is
localized.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=MM4zl69q3r59Yxlu3zp4WQ==&loc=wDBSZCsAt7zoiVrqcFJsRw==


Patent Number 268326
Indian Patent Application Number 1351/KOLNP/2010
PG Journal Number 35/2015
Publication Date 28-Aug-2015
Grant Date 26-Aug-2015
Date of Filing 16-Apr-2010
Name of Patentee ASAHI KASEI CHEMICALS CORPORATION
Applicant Address 1-105, KANDA JINBOCHO, CHIYODA-KU, TOKYO 101-8101 JAPAN
Inventors:
# Inventor's Name Inventor's Address
1 KEN SUZUKI 1-105, KANDA JINBOCHO, CHIYODA-KU, TOKYO 101-8101 JAPAN
PCT International Classification Number B01J 23/89
PCT International Application Number PCT/JP2008/069249
PCT International Filing date 2008-10-23
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 2007-279397 2007-10-26 Japan