Title of Invention

"A CRYSTALLINE MATERIAL AND METHOD OF SYNTHESIZING THE SAME"

Abstract A crystalline material having, in its calcined form, an X-ray diffraction pattern including the lines listed in Table 2 and a crystalline material having, in its synthesized form, an X-ray diffraction pattern including the lines listed in Table 1 and method of synthesizing said crystalline material.
Full Text FIELD
[0001] This invention relates to a novel small pore aluminophosphate
molecular sieve, or a substituted derivative thereof, to a method of synthesis of the molecular sieve and to its use in organic conversion reactions.
BACKGROUND
[0002] Crystalline molecular sieves have a 3-dimensional, four-connected
framework structure of corner-sharing [TO4] tetrahedra, where T is any tetrahedrally coordinated cation. Among the known forms of molecular sieve are aluminosilicates, which contain a three-dimensional microporous crystal framework structure of [SiO4] and [AlO4] corner sharing tetrahedral units, aluminophosphates (ALPOs), in which the framework structure is composed of [AlO4] and [PO4] corner sharing tetrahedral units and silicoaluminophosphates (SAPOs), in which the framework structure is composed of [SiO4], [AlO4] and [PO4] corner sharing tetrahedral units.
[0003] Molecular sieves have been classified by the Structure Commission
of the International Zeolite Association according to the rules of the IUPAC Commission on Zeolite Nomenclature. According to this classification, framework-type zeolite and zeolite-type molecular sieves, for which a structure has been established, are assigned a three letter code and are described in the Atlas of Zeolite Framework Types, 5th edition, Elsevier, London, England (2001), which is herein fully incorporated by reference.
[0004] Molecular sieves are typically described in terms of the size of the
ring that defines a pore, where the size is based on the number of T atoms in the ring. Other framework-type characteristics include the arrangement of rings that form a cage, and when present, the dimension of channels, and the spaces between the cages. See van Bekkum, et al., Introduction to Zeolite Science and Practice,
Second Completely Revised and Expanded Edition, Volume 137, pages 1-67, Elsevier Science, B.V., Amsterdam., Netherlands (2001).
[0005] In general, molecular sieves can be divided into small, medium and
large pore materials. Thus small pore molecular sieves typically have pores defined by a ring of no more than 8 T atoms and have an average pore size less than about 0.5 nm (5 A). Medium pore molecular sieves typically have pores defined by a ring of 10 T atoms and have an average pore size about 0.5 to 0.6 nm (5 to 6A), whereas large pore materials have pores defined by rings of 12 or more T atoms and a pore size greater than 0.6 nm (6A).
[0006] Crystalline molecular sieves, as exemplified by zeolites and
(metallo)aluminophosphates, are commercially important materials for petroleum
processing and petrochemical applications. Because each unique structure type
offers new potential for applications in catalysis and separations, there has been
sustained research effort, both in industry and academia, for their discovery.
[0007] Many molecular sieves are synthesized in the presence of an
organic directing agent, such as an organic nitrogen compound. For example, it is known from, for example, U.S. Patent No. 6,680,278 that a crystalline silicoaluminophosphate molecular sieve of the CHA framework type (a small pore material), can be synthesized in the presence of an organic directing agent mixture comprising tetraethylammonium cations and one or more dimethylamino moieties
selected from one or more of N,N-dimethylethanolamine, N,N-dimethylpropanolamine, N,N-dimethylbutanolamine, N,N-dimethylheptanolamine, N,N-dimethylhexanolamine, N,N-dimethylethylenediamine, N,N-dimethylbutylenediamine, N,N-dimethylheptylenediamine, N,N-dimethylhexylenediamine 1 -dimethylamino-2-propanol, N,N-dimethylethylamine, N,N-dimethylpropylamine, N,N-dimethylpentylamine, N,N-dimethylhexylamine and N,N-dimethylheptylamine. Other organic directing agents that have been used in the synthesis of CHA framework type materials include isopropylamine or di-n-propylamine triethylamine, cyclohexylamine, 1-methylamidazole, morpholine, pyridine, piperidine, diethylethanolamine, andN,N,N',N'-tetraethylethylene diamine.
[0008] It is also known to use fluoride-containing compounds, such as
hydrogen fluoride, as mineralizing agents in zeolite synthesis. For example, EP-A-337,479 discloses the use of hydrogen fluoride in water at low pH to mineralize silica in glass for the synthesis of ZSM-5. In addition, U.S. Patent Application Publication No. 2003/0231999 published December 18, 2003 and incorporated herein by reference, discloses that aluminophosphate or silicoaluminophosphate molecular sieves having the CHA framework type can be synthesized in the presence of fluoride ions using the dimethylamino compounds disclosed in U.S. Patent No. 6,680,278 as directing agents.
[0009] Currently, an entirely rational approach that leads to the synthesis
of unique framework materials is not available, due to the fact that all crystalline microporous materials are metastable phases and they are kinetic products. Their discovery is therefore often serendipitous.
[0010] Our research has led to two findings: that 4-DMAPy can direct the
synthesis of low-silica SAPO-CHA in the presence of colloidal SAPO-34 seeds; and, from parallel experiments, that with 4-DMAPy as an organic directing agent, without SAPO-34 seeds but in the presence of significant levels of fluoride ion F (F/Al2O3 of at least 0.75), there is unexpectedly formed a crystalline aluminophosphate designated EMM-9 with a new, but as yet undetermined, framework structure and having pores that in cross section have at least one distance or "diameter" that is typically categorised as small. At lower levels of fluoride ion (F/A12O3 [0011] According to -aan article in Chemical -Journal of Chinese
Universities, Vol. 22, No. 10, pages 192-195, dated October 2001, DMAPyhas been used as a template in the synthesis of NK-101, an aluminophosphate. However, comparison of the X-ray diffraction patterns of NK-101 with that of the small pore material of the invention shows that the present material is different from NK-101.
SUMMARY
[0012] In one aspect, the invention resides in a crystalline material having,
in its as-synthesized form, an X-ray diffraction pattern including the lines listed in Table 1 below. In its as-calcined form, the material of of the invention has an X-ray diffraction pattern including the lines listed in Table 2 below. The phrase "including the lines" as used herein means that peaks are expected to be present at or close to the lines indicated in the Tables, but not necessarily in the relative intensities specified, which can vary depending on a number of factors as discussed later.
[0013] Typically, the crystalline material comprises [A1C>4] and [PO4]
corner sharing tetrahedral units and conveniently also comprises [SiO4] corner sharing tetrahedral units.
[0014] Conveniently, in its as-synthesized form and on an anhydrous
basis, the porous, crystalline material is represented by the empirical formula:
mR:Fa:(MxAlyPz)O2
wherein R represents at least one directing agent, preferably 4-dimethylaminopyridine; m is the number of moles of R per mole of (MXALPZ)O2 and has a value from about 0 to about 1, such as from about 0 to about 0.5, for example from about 0 to about 0.3; wherein a is the number of moles of fluoride ion (F) per mole of (MxAlyPz)O2 and has a value of about 0 to about 1, such as from about 0.1 to about 0.8, for example from about 0.2 to about 0.6; wherein x, y, and z represent the respective mole fractions of M, Al and P as tetrahedral oxides; and wherein M is a metal selected from one of Groups 1 to 14 and Lanthanoids of the Periodic Table of Elements. Preferably M is selected from B, Co, Cr, Cu, Fe, Ga, Ge, Mg, Mn, Ni, Si, Sn, Ti, Zn and/or Zr and most preferably, M is silicon. In one embodiment, x is from 0 to about 0.25, y is from about 0.3 to about 0.7 and z, is from about 0.25 to about 0.7. In another embodiment, x is from about 0 to about 0.15, y is from about 0.4 to about 0.6 and z is from about 0.3 to about 0.6. In yet another embodiment x is from about 0 to about 0.12, y is from about 0.45 to about 0.55 and z is from about 0.35 to about 0.55. For ALPO molecular sieves, x is zero.
[0015] In another aspect, the invention resides in a method of synthesizing
the crystalline material of said one aspect of the invention, the process comprising:
(a) forming a reaction mixture comprising a source of aluminum, a source of
phosphorus, a source of fluoride ions, optionally a source of metal M, and at least
one structure directing agent comprising 4-dimethylaminopyridine such that said
reaction mixture has a F/AkOa molar ratio of at least 0.75, such as greater than
0.75 to about 2.5, for example from 0.85 to 2.0 and conveniently from 1.0 to 1.5;
(b) inducing crystallization of said crystalline material from the reaction mixture;
and (c) recovering said crystalline material from the reaction mixture.
[0016] In still a further aspect, the invention resides in the use of the
crystalline material of said one aspect of the invention as a sorbent or as a catalyst
in organic conversion reactions.
DESCRIPTION OF THE DRAWINGS
[0017] Figure 1 gives the X-ray diffraction patterns of the as-synthesized
products of Example 1 after crystallization for 1 day and 3 days.
[0018] Figure 2 gives the X-ray diffraction patterns of the as-synthesized
products of Example 2 with varying F/AC molar ratios.
[0019] Figure 3 is a comparison of the X-ray diffraction patterns of
Sample A in Example 1 and Sample B in Example 3.
[0020] ~ Figure 41s a comparison of the X-ray diffraction pattern of Sample
B in Example 3 (ALPO) with the X-ray diffraction pattern of the as-synthesized SAPO products of Example 4 after crystallization for 1 day (Sample C) and 2 days.
[0021] Figure 5 is a comparison of the X-ray diffraction patterns of
Samples A, B and C after caleinatiion at 6500C for 2 hours as described in
Example 5.
[0022] Figure 6 is a comparison of the X-ray diffraction patterns of
Sample B after calcination at varying temperatures and times as described in Example 5.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0023] In one embodiment, the present invention relates to a novel porous
crystalline (metallo)aluminophosphate material, such as a SAPO and A1PO4, its synthesis in the presence of fluoride ions and the organic directing agent, 4-dimethylaminopyridine, and its use as a catalyst in organic conversion reactions. The crystalline structure remains intact after calcination to remove the directing agent and adsorption data suggest that the calcined material may have small, slit-like pore openings. In particular, the calcined material does not adsorb 2,2-dimethylbutane, but does adsorb methanol, n-hexane, and a small amount of mesitylene. The SAPO version of the material has methanol conversion activity and n-hexane cracking activity.
[0024] The porous, crystalline material of the invention comprises at least
[AlCU] and [PO4] corner sharing tetrahedral units, and preferably [SiO4], [A1O4] and [PO4] corner sharing tetrahedral units, and has, in its as-synthesized form, an X-ray diffraction pattern including the lines listed in Table 1 below:
(Table Removed)
[0025] In its as-calcined form, the porous, crystalline material of the
invention has an X-ray diffraction pattern including the lines listed in Table 2 below:
(Table Removed)
[0026] These, and all other X-ray diffraction data referred to herein, were
collected with a Siemens D500 diffractometer with a voltage of 40 kV and a current of 30 mA using a copper target (A = 0.154nm) and a curved graphite monochrometer. The diffraction data were recorded by step-scanning at 0.02 degrees of two-theta, where theta is the Bragg angle, and a counting time of 1 second for each step. The interplanar spacings, d's, were calculated in nanometres (nm), and the relative intensities of the lines, I/ lo, where lo is one-hundredth of the intensity of the strongest line, above background, were derived with the use of
a profile fitting routine (or second derivative algorithm). The intensities are
uncorrected for Lorentz and polarization effects. The relative intensities are given in terms of the symbols vs=very strong (75-100), s-strong (50-74), m=medium (25-49) and w=weak (0-24). It should be understood that diffraction data listed for this sample as single lines may consist of multiple overlapping lines which under certain conditions, such as differences in crystallite sizes or very high experimental resolution or crystallograpliic change, may appear as resolved or partially resolved lines. Typically, crystallographic changes can include minor changes in unit cell parameters and/or a change in crystal symmetry, without a change in topology of the structure. These minor effects, including changes in relative intensities, can also occur as a result of differences in cation content,

framework composition, nature and degree of pore filling, and thermal and/or
hydrothennal history. In practice, therefore, at least some of the lines in the X-ray
patterns of the crystalline material of the invention may exhibit significant
variations in relative intensity from the values indicated in Tables 1 and 2.
[0027] To generate the as-calcined X-ray data listed in Table 2, about 0.5
grams of the dried, as-synthesized crystalline material are heated in an oven from room temperature under a flow of nitrogen at a rate of 10°C/minute to 400°C and, while retaining the nitrogen flow, the sample is held at 400°C for 30 minutes. The nitrogen flow is then ceased and air is passed over the sample while the temperature of the oven is raised at a rate of 10°C/minute to 600°C. The sample is then retained at 600°C for 2 hours under air, whereafter the oven is cooled to room temperature to allow the XRD pattern to be recorded.
[0028] hi its as-synthesized form and on an anhydrous basis, the porous,
crystalline material of the present invention can be represented by the empirical
formula:
mR:Fa:(MxAlyPz)02
wherein R represents at least one directing agent, preferably an organic directing agent and most preferably 4-dimethylaminopyridine, m is the number of moles of R per mole of (MxAlyPz)02 and m has a value from about 0 to about 1 , such as from about 0 to about 0.5, for example from 0 to about 0.3 ; wherein F represents fluoride ion, a is the number of moles-ofPper
value of 0 to 1, such as from 0.1 to 0.8, for example from 0.2 to 0.6; wherein x, y, and z represent the mole fraction M, Al and P as tetrahedral oxides; and wherein M is a metal selected from one of Groups 1 to 14 and Lanthanoids of the Periodic Table of Elements. Preferably M is selected from B, Co, Cr, Cu, Fe, Ga, Ge, Mg,
[0029] In one embodiment, x is from 0 to about 0.25, y is from about 0.3
to about 0.7 and z is from about 0.25 to about 0.7. hi another embodiment x is from about 0 to about 0.15, y is from about 0.4 to about 0.6 and z is from about 0.3 to about 0.6. In yet another embodiment x is from about 0 to about 0.12, y is
from about 0.45 to about 0.55 and z is from about 0.35 to about 0.55. For ALPO molecular sieves, x is zero.
[0030] It will be appreciated that the R and F components, which are
associated with the as-synthesized material as a result of their presence during crystallization, are easily removed by post-crystallization methods hereinafter more particularly described.
[0031 ] The silicoaluminophosphate of the present invention typically has
an alpha value of at least 0.1, and more preferably at least 0.5, indicating that the
material is useful as an acid catalyst in organic conversion reactions. The alpha
value test is a measure of the cracking activity of a catalyst and is described in
U.S. Patent No. 3,354,078 and in the Journal of Catalysis, Vol. 4, p. 527 (1965);
Vol. 6, p. 278 (1966); and Vol. 61, p. 395 (1980), each incorporated herein by
reference as to that description. The experimental conditions of the test used
herein include a constant temperature of 538°C and a variable flow rate as
described in detail in the Journal of Catalysis, Vol. 61, p. 395.
[0032] The porous crystalline material of the present invention can be
produced from a synthesis mixture containing water, a source of phosphorus, a source of aluminum, a source of fluoride ions, optionally a source of metal M, such as silicon, and 4-dimethylaminopyridine (R). The synthesis mixture typically has a composition, expressed in terms of mole ratios of oxides, as follows:
(Table Removed)
[0033] More specifically, F/A12O3 molar ratio of the synthesis mixture is
from O.S5 to 2.0, such as from 1.0 to 1.5
[0034] A suitable source of phosphorus in the above mixture is phosphoric
acid. Examples of suitable aluminum sources include hydrated aluminum oxides
such as boehmite, pseudoboehmite, and aluminum trialkoxide. Suitable sources
of silicon include silicates, e.g., fumed silica, such as Aerosil and Cabosil,
tetraalkyl orthosilicates, and aqueous colloidal suspensions of silica, for example
that sold by E.I. du Pont de Nemours under the tradename Ludox.
[0035] The source of fluoride ions may be any compound capable of
releasing fluoride ions in the synthesis mixture. Non-limiting examples of such sources of fluoride ions include salts containing one or several fluoride ions, such as metal fluorides, preferably, sodium fluoride, potassium fluoride, calcium fluoride, magnesium fluoride, strontium fluoride, barium fluoride, ammonium fluoride, tetraalkylammonium fluorides, such as tetramethylammonium fluoride, tetraethylammonium fluoride, hydrogen fluoride, fluorosilicic acid, hexafluorophosphoric acid, and mixtures thereof. Most preferably, the source of fluoride is hydrogen fluoride.
[0036] Crystallization is carried out under either stirred or static
conditions, preferably stirred conditions, at a temperature between about 100°C and about 250°C, typically between about 130°C and about 200°C, preferably between about 150°C and about 180°C. Preferably, crystallization is conducted for about 2 to about 150 hours, preferably about 20 to about 100 hours, whereafter "the"fesurtant crystalline material ispraled'fromlhelnotherliquor and recovered, such as by centrifugation or filtration. The separated product can also be washed, recovered by centrifugation or filtration and dried. The crystalline product is typically in the form of platelets having a d50 (50 % by volume of crystals is smaller than the d50 value) particle size less than 1 /mi.
the invention may be facilitated by the presence of at least 0. 1 ppm, such as at
least 10 ppm, for example at least 100 ppm, conveniently at least 500 ppm of seed
crystals from a previous synthesis based on total weight of the reaction mixture.
[0038] As a result of the crystallization process, the recovered crystalline
product contains within its pores at least a portion of the organic directing agent
used in the synthesis. In a preferred embodiment, activation is performed in such a manner that the organic directing agent is removed from the molecular sieve, leaving active catalytic sites within the microporous channels of the molecular sieve open for contact with a feedstock. The activation process is typically accomplished by calcining, or essentially heating the molecular sieve comprising the template at a temperature of from about 200°C to about 800°C, typically in the presence of an oxygen-containing gas. This type of process can be used for partial or complete removal of the organic directing agent from the intracrystalline pore
system.
[0039] Once the crystalline material of the invention has been synthesized,
it can be formulated into a catalyst composition by combination with other materials, such as binders and/or matrix materials, that provide additional hardness or catalytic activity to the finished catalyst.
[0040] Materials which can be blended with the crystalline material of the
invention can be various inert or catalytically active materials. These materials
include compositions such as kaolin and other clays, various forms of rare earth
metals, other non-zeolite catalyst components, zeolite catalyst components,
alumina or alumina sol, titania, zirconia, quartz, silica or silica sol, and mixtures
thereof. These components are also effective in reducing overall catalyst cost,
acting as a thermal sink to assist in heat shielding the catalyst during regeneration,
densifying teh catalyst and increasing catalyst strength. When blended with such
components, the amount of intergrown crystalline material contained in the final
catalyst product ranges from 10 to 90 weight percent of the total catalyst,
preferably 20 to 80 weight percent of the total catalyst.
[0041] The small pore crystalline material described herein can be used to
dry gases and liquids; for selective molecular separation based on size and polar
properties; as an ion-exchanger; as a catalyst in organic conversion reactions, such as cracking, hydro cracking, disproportionation, alkylation, isomerization, oxidation and synthesis of monoalkylamines and dialkylamines; as a chemical carrier; in gas chromatography; and in the petroleum industry to remove normal paraffins from distillates.
[0042] In particular, the small pore crystalline material described herein is
useful in the catalytic conversion of oxygenates to one or more olefins, particularly ethylene and propylene. As used herein, the term "oxygenates" is defined to include, but is not necessarily limited to aliphatic alcohols, ethers, carbonyl compounds (aldehydes, ketones, carboxylic acids, carbonates, and the like), and also compounds containing hetero-atoms, such as, halides, mercaptans, sulfides, amines, and mixtures thereof. The aliphatic moiety will normally contain from about 1 to about 10 carbon atoms, such as from about 1 to about 4 carbon atoms.
[0043] Representative oxygenates include lower straight chain or branched
aliphatic alcohols, their unsaturated counterparts, and their nitrogen, halogen and
sulfur analogues. Examples of suitable oxygenate compounds include methanol;
ethanol; n-propanol; isopropanol; C4 - C10 alcohols; methyl ethyl ether; dimethyl
ether; diethyl ether; di-isopfopyl ether; methyl mercaptan; methyl sulfide; methyl
amine; ethyl mercaptan; di-ethyl sulfide; di-ethyl amine; ethyl chloride;
formaldehyde; di-methyl carbonate; di-methyl ketone; acetic acid; n-alkyl amines,
n-alkyl halides, n-alkyl sulfides having n-alkyl groups of comprising the range of
from about 3 to about 10 carbon atoms; and mixtures thereof. Particularly suitable
oxygenate compounds are methanol, dimethyl ether, or mixtures thereof, most
preferably methanol. As used herein, the term "oxygenate" designates only the
organic material used-as the-feed.- -The total charge-of feed to-the reaction-zone- --
may contain additional compounds, such as diluents.
[0044] In the present oxygenate conversion process, a feedstock
comprising an organic oxygenate, optionally with one or more diluents, is contacted in the vapor phase in a reaction zone with a catalyst comprising the ..molecular sieve of the present invention at effective process conditions so as to produce the desired olefins. Alternatively, the process may be carried out in a liquid or a mixed vapor/liquid phase. When the process is canied out in the liquid phase or a mixed vapor/liquid phase, different conversion rates and selectivities of feedstock-to-product may result depending upon the catalyst and the reaction conditions.
[0045] When present, the diluent(s) is generally non-reactive to the
feedstock or molecular sieve catalyst composition and is typically used to reduce the concentration of the oxygenate in the feedstock. Non-limiting examples of suitable diluents include helium, argon, nitrogen, carbon monoxide, carbon dioxide, water, essentially non-reactive paraffins (especially alkanes such as methane, ethane, and propane), essentially non-reactive aromatic compounds, and mixtures thereof. The most preferred diluents are water and nitrogen, with water being particularly preferred. Diluent(s) may comprise from about 1 mol % to about 99 mol % of the total feed mixture.
[0046] The temperature employed in the oxygenate conversion process
may vary over a wide range, such as from about 200°C to about 1000°C, for
example from about 250°C to about 800°C, including from about 250°C to about
750 °C, conveniently from about 300°C to about 650°C, typically from about
350°C to about 600°C and particularly from about 400°C to about 600°C.
[0047] Light olefin products will form, although not necessarily in
optimum amounts, at a wide range of pressures, including but not limited to autogenous pressures and pressures in the range of from about 0.1 kPa to about 10 MPa. Conveniently, the pressure is in the range of from about 7 kPa to about 5 MPa, such as in the range of from about 50 kPa to about 1 MPa. The foregoing pressures are exclusive of diluent, if any is present, and refer to the partial pressure of the feedstock~as~it relates to oxygenate compounds and/ormixtures thereof:
Lower and upper extremes of pressure may adversely affect selectivity,
conversion, coking rate, and/or reaction rate; however, light olefms such as
ethylene still may form.
[0048] The process should be continued for a period of time sufficient to
seconds to a number of hours. The reaction time is largely determined by the reaction temperature, the pressure, the catalyst selected, the weight hourly space velocity, the phase (liquid or vapor) and the selected process design characteristics.
[0049] A wide range of weight hourly space velocities (WHSV) for the
feedstock will function in the present process. WHSV is defined as weight of feed (excluding diluent) per hour per weight of a total reaction volume of molecular sieve catalyst (excluding inerts and/or fillers). The WHSV generally should be in the range of from about 0.01 hr-l to about 500 hr"1, such as in the range of from about 0.5 hr"1 to about 300 hr"1, for example in the range of from about 0.1 hr"1 to about 200 hr"1.
[0050] A practical embodiment of a reactor system for the oxygenate
conversion process is a circulating fluid bed reactor with continuous regeneration, similar to a modern fluid catalytic cracker. Fixed beds are generally not preferred for the process because oxygenate to olefin conversion is a highly exothermic process which requires several stages with intercoolers or other cooling devices. The reaction also results in a high pressure drop due to the production of low pressure, low density gas.
[0051] Because the catalyst must be regenerated frequently, the reactor
should allow easy removal of a portion of the catalyst to a regenerator, where the catalyst is subjected to a regeneration medium, such as a gas comprising oxygen, for example air, to bum off coke from the catalyst, which restores the catalyst activity. The conditions of temperature, oxygen partial pressure, and residence time in the regenerator should be selected to achieve a coke content on regenerated "catalyst of less'than 'about 0.5 wt "%.~At least a portion ofthe regenerated -catalyst — should be returned to the reactor.
[0052] In order to more fully illustrate the nature ofthe invention and the
manner of practicing same, the following Examples are presented. In the Examples, elemental analysis of Al, Si, and P was performed using Inductively
Plasma (ICP) spectroscopy.
Example 1
[0053] The following ingredients were mixed, in sequence, and blended
into a uniform gel using a microhomogenizer (Tissue Tearor Model 98730, available from Biospec Products, Inc, USA): 85 wt% H3P04 (obtained from
Aldrich Chemical Company), deionized H20, Catapaf' A (73.9 wt% A12O3, available from CONDEA Vista Company, Texas, USA), 50 wt% HF in water (Aldrich Chemical Company), and then 4-dimethylaminopyridine (4-DMAPy) (obtained from Aldrich Chemical Company, USA). The molar ratio of the ingredients was as follows:
1.0 HR2.0 DMAPy:1.0 A1203:1.0 P205:40 H2O
[0054] The gel was then placed into a Parr bomb with Teflon liner, and
was heated to 180°C for 1 to 3 days statically. The solid product was centrifuged and washed five times with deionized water, and was then dried in a 60°C vacuun oven overnight. X-ray powder patterns of the product showed, in Figure 1, that a crystalline product was obtained after one day of crystallization (Sample A). Afte three days of crystallization, additional diffraction peaks corresponding to an unidentified impurity appeared.
[0055] Solid product yield of Sample A was 13.6%, based on the total
weight of the starting gel. Elemental analysis gave the following results: Al, 13.31%; P, 14.94%. These results corresponded to Ali.oPo.97g in composition and 59.4% for calculated total oxides.
[0056] The XRD pattern of S ample A had no match with any known
patterns. The peak list is shown in Table 3 below.
(Table Removed)
Example 2
[0057] The procedure of Example 1 was repeated, except that varying
amounts of hydrofluoric acid were added to produce four different synthesis mixtures having the following molar ratio of ingredients: xHF:2.0DMAPy:1.0Al2O3:1.0P2O5:40H2O where x = 0.5, 0.625, 0.75 and 0.875.
[0058] In each case, the crystallization was carried out for one to two days
at 180°C statically. The XRD patterns of the products are shown in Figure 2 along with that of Sample A. Figure 2 shows that, at an HF/Al2O3 molar ratio less than 0.75, the new framework material disclosed in co-pending U.S. Patent Application Serial No. 60/615111 (Attorney Docket No. 2004M116/PM2003-CL-087) was formed. At HF/Al2O3 molar ratios greater than 0.75, the new phase of this invention was formed. When the HF/Al2O3 molar ratio was equal to 0.75, a
mixture"of the two phases was "produced."
[0059] Elemental analysis of the product obtained with HF/A12O3 molar
ratio of 0.875 gave the following results: Al, 12.2%; P, 14.2%. These results corresponded to Alj.oPi.oi4 in composition and 56.4% for calculated total oxides.
[0060] The procedure was identical to Example 2, except that a higher
amount of hydrofluoric acid was added and the ingredient ratio was the following:
2.0HF:2.0DMAPy:1.0Al203:1.0P2O5:40H20
[0061] Crystallization was carried out for two days at 170 °C with
tumbling at 40 rpm. The product yield was 10.0% based on the total weight of the
gel. The XRD pattern of the product (Sample B) is shown in Figure 3, along with that of Sample A. Figure 3 shows that Sample B is the same crystalline phase as Sample A. Elemental analysis of Sample B gave the following results: Al, 13.3%; P, 15.1%. These results corresponded to Al2.oPo.9S9 in composition and 59.8% for calculated total oxides.
[0062] This example, along with Example 2, shows that products of this
invention, having the same XRD pattern, can be obtained with variations in both gel composition and in reaction conditions. These results establish that the product of this invention is a phase-pure material.
Example 4
[0063] The procedure was identical to Example 1, except that silica in the
form of Cabosil™ (Cabot Corporation, Illinois, USA) was added after the addition of Catapal and before the addition of HF. The ingredient ratio was the following:
1.0HF:2.0DMAPy:1.0Al2O3:0.5SiO2:1.0P2O5:40H2O
[0064] 0.1 wt% (with respect to the weight of the gel) of Sample A was
added to the synthesis gel as seeds and crystallization was carried out for one day
and two days, respectively, at 170 °C with tumbling at 40 rpm. The XPJD patterns
of the products are shown in Figure 4, along with that of sample B.
[0065] Figure 4 shows that the SAPO products have the same framework
structure as -Sample B~(an A1PO4).- Elemental -analysis ofthe SAPO sample
obtained after one day of crystallization (Sample C) gave the following results: Al, 12.6%; Si, 3.67%; P, 12.7%. These results corresponded to Ali.oSio.28oPo.878 in composition and 62.2% for calculated total oxides. TGA (Thermal Gravimetric Analysis) revealed a non-combustible residual weight of 62.79%.
.Example s
[0066] To effect removal of the organic directing agent, Samples A, B, and
C were placed in a muffle furnace and the temperature was ramped at 10°C/minute to 400°C while the furnace was flushed with nitrogen. After dwelling at 400°C for 30 minutes, the temperature ramping was continued, and the flowing gas was
switched from nitrogen to air. The temperature ramp stopped at 650°C and the
sample was calcined at this temperature for two hours under flowing air. During
the entire calcination process the sample turned dark brown first, finally to slightly
off-white. The XKD patterns of the calcined samples are shown in Figure 5.
[0067] Figure 5 shows that the calcined samples have only broad peaks.
The peaks include at least the following (Table 4):
(Table Removed)
[0068] To test the thermal stability of the material, Sample B was calcined
under conditions of different thermal severity. Figure 6 shows the XRD patterns of the sample B following calcination at 550 °C for three hours, then after calcination at 650 °C for an additional one and half hours, and then after calcination at 650 °C for 72 more hours. Figure 6 shows that there is hardly any change with these thermal treatments, indicating the material is at least stable to 650 °C.
Example 6
degassed (at 500°C) before being exposed to different adsorbate molecules under specified conditions as listed in Table 5 below in a Thermal Gravimetric Analysis (TGA) unit. The weight gain (or the lack of) of the sample was recorded, from which adsorption capacity was calculated and expressed as percent of "gram
adsorbed per gram of calcined sample". Table 5 summarizes the results of the adsorption experiments.
(Table Removed)
[0070] The data in Table 5 show that the new material is porous, having
pore openings large enough to allow molecules with kinetic diameter less than 0.43 nm (4.3 A), such as n-hexane and methanol, to be adsorbed. The pore size is apparently very close to the kinetic diameter of n-hexane, as the calcination temperature affects the amount adsorbed. Without wishing to be bound by theory, it is conjectured that the pore opening is likely to be slit-like, rather than circular, because a small but significant amount of mesitylene (a flat molecule) is adsorbed whereas 2,2-dimethylbutane (2,2-DMB) is not. These adsorption characteristics and the gross change of XRD pattern caused by calcination suggest a condensed layer-structure -for the- calcined phaser
Example 7
[0071] Sample C was calcined as described in Example 5, but was held at
600°C for 2 hours in air. The powder was pelletized to 14-25 mesh size for the alpha testa tandard n-hexane cracking test conducted l_at 1000°F (540°C)
fixed n-hexane partial pressure). Such test gave an alpha value of 5.2 for the material. For comparison, a diffusionally unconstrained material, such as SAPO-11 , at similar Si/Al ratio as Sample C, typically has an alpha value of greater than 20. The low alpha value of the new material suggests steric hindrance for n-
hexane to access the interior of the material, just as the adsorption data also suggest. Example 8
[0072] Sample C, after calcination in air at 650°C for 2 hours, was tested
for methanol-to-olefins (MTO) conversion. Methanol liquid was fed via a pump and was vaporized before contacting the catalyst, which was held at 475°C. The methanol pressure was 276 kPa (40 psia) and its feed rate was 100 WHSV. The product effluent was sampled with a multi-port sampling loop during a non-steady-state run (catalyst is continuously deactivated during the MTO run) and each port was analyzed with a Gas Chromatograph equipped with an FID detector. The coke selectivity was calculated with an algorithm reiterated to attain the same H/C ratio in the products as in the feed. Table 6 lists the key MTO reactivity data, along with the product selectivity averaged over the entire run.
(Table Removed)
[0073] Data in Table 6, along with the alpha test results, indicate that the
new material is active for catalytic transformations of organic compounds.
[0074] While the present invention has been described and illustrated by
reference to particular embodiments, those of ordinary skill in the art will appreciate that the invention lends itself to variations not necessarily illustrated herein. for the reason, them, reference should be made solely to the appended claims for purposes of determining the true scope of the present invention.




We Claim:
1. A crystalline material having, in its calcined form, an X-ray diffraction pattern including
the lines listed in below Table
(Table Removed)
2. The crystalline material as claimed in claim 1 comprising [AlO4] and [PO4] corner sharing tetrahedral units.
3. The crystalline material as claimed in claim 2 and also comprising [SiO4] corner sharing tetrahedral units.
4. The crystalline material as claimed in claim 1, having in its as-synthesized form, an X-ray diffraction pattern including the lines listed in below Table.
(Table Removed)
5. The crystalline material as claimed in claim 4 and represented by the empirical formula,
on an anhydrous basis:
(Formula Removed)
wherein R represents at least one directing agent; wherein m is the number of moles of R per mole of (MxAlyPz)O2; wherein a is the number of moles of fluoride ion (F) per mole of (MxAlyPz)O2; wherein x, y, and z represent the mole fraction of M, Al and P as tetrahedral oxides; and wherein M is a metal selected from one of Groups 1 to 14 and Lanthanoids of the Periodic Table of Elements.
6. The crystalline material as claimed in claim 5 wherein m has a value from 0 to 1.
7. The crystalline material as claimed in claim 6 wherein m has a value from 0 to 0.5.
8. The crystalline material as claimed in claim 7 wherein m has a value from 0 to 0.3.
9. The crystalline material as claimed in any of claims 5 to 8 wherein R is 4-dimethylaminopyridine.
10. The crystalline material as claimed in any of claims 5 to 9 wherein a has a value from 0 to 1.
11. The crystalline material as claimed in claim 10 wherein a has a value from 0.1 to 0.8.

12. The crystalline material as claimed in claim 11 wherein a has a value from 0.2 to 0.6.
13. The crystalline material as claimed in any of claims 5 to 12 wherein M is selected from one of the group consisting of B, Co, Cr, Cu, Fe, Ga, Ge, Mg, Mn, Ni, Si, Sn, Ti, Zn, Zr and mixtures thereof.
14. The crystalline material as claimed in any of claims 5 to 12 wherein M is silicon.
15. The crystalline material as claimed in any of claims 5 to 14 wherein x is from 0 to 0.25, y is from 0.3 to 0.7 and z is from 0.25 to 0.7.
16. The crystalline material as claimed in claim 15 wherein x is from 0 to 0.15, y is from 0.4 to 0.6 and z is from 0.3 to 0.6.
17. The crystalline material as claimed in claim 16 wherein x is from 0 to 0.12, y is from 0.45 to 0.55 and z is from 0.35 to 0.55.
18. A method of synthesizing the crystalline material as claimed in any preceding claim, the process comprising: (a) forming a reaction mixture comprising a source of aluminum, a source of phosphorus, a source of fluoride ions, optionally a source of metal M, and at least one structure directing agent comprising 4-dimethylaminopyridine such that said reaction mixture has a F/Al2O3 mole ratio of at least 0.75; (b) including crystallization of said crystalline material from the reaction mixture; and (c) recovering said crystalline material from the reaction mixture.
19. The method as claimed in claim 18 wherein the reaction mixture has a composition, in terms of mole ratios, within the following ranges:
P2O5:Al2O3 =0.7 to 1.3
SiO2 : Al2O3 = 0 to 9
H2O : Al2O3 = 10 to 100
R : Al2O3 = 0.5 to 5.0
F : Al2O3 = >0.75 to 3

20. The method as claimed in claim 19 wherein the reaction mixture has a composition, in
terms of mole ratios, within the following ranges:
P2O5:A1203 =0.9 to 1.1
SiO2 : A12O3 = 0.05 to 0.5
H2O : Al2O3 = 20 to 60
R : Al2O3 = 1.0 to 4.0
F : A12O3 = >0.75 to 2.5.
21. The method as claimed in claim 18,19 or 20 wherein the reaction mixture has an F/Al2O3 mole ratio of 0.85 to 2.0.
22. The method as claimed in claim 21 wherein the reaction mixture has an F/Al2O3 mole ratio of 1.0 to 1.5.
23. The method as claimed in claims 18 to 22, wherein crystallization of said crystalline material is conducted at a temperature of 100°C to 250°C.
24. The method as claimed in claim 23, wherein crystallization of said crystalline material is conducted at a temperature of 130°C to 200°C.
25. An organic conversion process comprising contacting an organic feedstock with a catalyst comprising the crystalline material as claimed in any of claims 1 to 17 or produced by the method as claimed in claims 18 to 24.
26. The process as claimed in claim 25 wherein an oxygenate-containing feedstock is converted to olefins.

Documents:

2259-DELNP-2007-Abstract-(23-12-2011).pdf

2259-DELNP-2007-Abstract-(27-09-2011).pdf

2259-delnp-2007-abstract.pdf

2259-DELNP-2007-Claims-(23-12-2011).pdf

2259-DELNP-2007-Claims-(27-09-2011).pdf

2259-delnp-2007-claims.pdf

2259-delnp-2007-Correspondence Others-(20-06-2011).pdf

2259-DELNP-2007-Correspondence Others-(23-12-2011).pdf

2259-DELNP-2007-Correspondence Others-(27-09-2011).pdf

2259-delnp-2007-correspondence-others-1.pdf

2259-delnp-2007-correspondence-others.pdf

2259-DELNP-2007-Description (Complete)-(27-09-2011).pdf

2259-delnp-2007-description (complete).pdf

2259-DELNP-2007-Drawings-(27-09-2011).pdf

2259-delnp-2007-drawings.pdf

2259-DELNP-2007-Form-1-(27-09-2011).pdf

2259-delnp-2007-form-1.pdf

2259-delnp-2007-form-18.pdf

2259-DELNP-2007-Form-2-(27-09-2011).pdf

2259-delnp-2007-form-2.pdf

2259-DELNP-2007-Form-3-(27-09-2011).pdf

2259-delnp-2007-form-3.pdf

2259-delnp-2007-form-5.pdf

2259-DELNP-2007-GPA-(27-09-2011).pdf

2259-delnp-2007-gpa.pdf

2259-delnp-2007-pct-101.pdf

2259-delnp-2007-pct-210.pdf

2259-delnp-2007-pct-220.pdf

2259-delnp-2007-pct-237.pdf

2259-DELNP-2007-Petition-137-(27-09-2011).pdf


Patent Number 250410
Indian Patent Application Number 2259/DELNP/2007
PG Journal Number 01/2012
Publication Date 06-Jan-2012
Grant Date 03-Jan-2012
Date of Filing 23-Mar-2007
Name of Patentee EXXONMOBIL CHEMICAL PATENTS INC.
Applicant Address 5200 BAYWAY DRIVE, BAYTOWN, TEXAS 77520-5200, USA
Inventors:
# Inventor's Name Inventor's Address
1 GUANG CAO 528 WOODSIDE LANE, BRANCHBURG, NJ 08876, USA
2 MATU J.SHAH 8 BUTTERNUT COURT, HACKETTSTOWN, NJ 07840, USA
PCT International Classification Number B01J 29/85
PCT International Application Number PCT/EP2005/009880
PCT International Filing date 2005-09-12
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/615,228 2004-10-01 U.S.A.