Title of Invention	AN IMPROVED PROCESS FOR THE PREPARATION OF NOVEL FCC CATALYST USING MODIFIED CRYSTALLINE MOLECULAR SIEVE AND SILICA ALUMINA MATRIX
Abstract	This invention relates to the process for the preparation of novel fluid catalytic cracking (FCC) catalyst, using modified zeolite with different degree of dealumination and silica-alumina matrix. The catalyst is prepared by dispersing modified zeolite in silica-alumina active matrix with improved hydrothermal stability and adequate catalytic and physical properties. The matrix prepared by the process of the present invention based on silica-alumina sol matrix controlling the pH of the medium at 3 or below to avoid gelation at the time of mixing the different ingredients results in improved hydrothermal stability.

Title of Invention

AN IMPROVED PROCESS FOR THE PREPARATION OF NOVEL FCC CATALYST USING MODIFIED CRYSTALLINE MOLECULAR SIEVE AND SILICA ALUMINA MATRIX

Abstract

This invention relates to the process for the preparation of novel fluid catalytic cracking (FCC) catalyst, using modified zeolite with different degree of dealumination and silica-alumina matrix. The catalyst is prepared by dispersing modified zeolite in silica-alumina active matrix with improved hydrothermal stability and adequate catalytic and physical properties. The matrix prepared by the process of the present invention based on silica-alumina sol matrix controlling the pH of the medium at 3 or below to avoid gelation at the time of mixing the different ingredients results in improved hydrothermal stability.

Full Text	This invention relates to the process for the preparation of novel fluid catalytic cracking (FCC) catalyst using modified crystalline molecular sieve and silica- alumina matrix. In particular, the invention relates to a process for the preparation of novel FCC catalyst using modified zeolite with different degree of dealumination and silica-alumina matrix. The invention more specifically relates to a process for the preparation of novel FCC catalyst by dispersing modified zeolite in silica-alumina active matrix with improved hydrothermal stability and adequate catalytic and physical properties. FCC catalyst is composed of zeolite and matrix. The zeolite is responsible for the bulk of the catalytic activity. The component referred as matrix fulfils both physical and catalytic functions. One of the major function of the matrix is to bind the zeolite particles together in micro spheroidal catalyst particles, hard enough to survive inter particle and reactor wall collisions. The presence of large (> 20A°) pores in the matrix allows it to serve as a diffusion medium for feed stock molecules and cracked products. Dealuminated zeolite-Y is preferably used in FCC catalyst formulations, as dealumination of zeolite-Y leads to decrease in unit cell size (UCS), increases silica to alumina ratio which in turn increases the hydrothermal stability of the zeolite. As the degree of dealuination increases the total acidity decreases but the percentage of strong acid sites increases and sites\become isolated due to which H-transfer reaction occuring during catalytic cracking reaction is suppressed and coke formation is reduced. Mesoporosity created by dealumination of zeolite-Y in conjunction with active matrix having larger pores, facilitate the diffusion of larger molecules present in the heavier fractions of the oil having higher molecular weight used as the FCC feed stock. FCC catalyst prepared by dispersing dealuminated zeolite in silica-alumina gel matrix is known to have low Apparant Bulk Density (ABD) and poor attrition resistance due to low solid content of catalyst slurry at pumpability of spray dryer. The matrix prepared by amulinium chloro-hydrate based alumina sol is associated with highly viscous catalyst slurry which makes the pumpable characteristics of catalyst slurry very inferior, lower surface area and catalytic activity. The matrix prepared by the process of the present invention based on silica-alumina sol fratrix controlling the pH of the medium at 3 or below to avoid gelation at the time of mixing the different ingredients results in improved hydrothermal stability. Ageing the silica-alumina sol after addition of other ingredients to convert it into gel result s in better binding strength of catalyst particles and. also catalytic properties due to stronger interaction of silica-alumina bond to generate appropriate acidity required for the catalytic cracking reaction. Use of optimum silica-alumina ratio (80:20) to maximise protonic acidity also improves the coke selectivity of the catalyst. The objective of the present invention is therefore, to provide an improved process for the preparation of FCC catalyst with improved hydrothermal stability, physical and catalytic properties. In each cycle of FCC operation, the catalyst is continuously deactivated by hydrothermal degradation as a result of dealumination of zeolite resulting in loss of activity. To compensate for the loss in aotivity, a part of the deactivated catalyst is replaced by the fresh catalyst to maintain the original activity of the catalyst. FCC catalyst having an adequate thermal and hydrothermal stability infers that it will have a high retention of surface area, zeolite crystallinity and acidity and thus the fresh catalyst addition rate will be reduced which will greatly affect the over all economics of the FCC operation. The objective of the present invention is therefore, to provide a process for the preparation of novel FCC catalyst with improved thermal and hydrothermal stability. In carryingout the present invention, as a result of extensive investigations carried out by us, two FCC catalysts were prepared using 20 and 60% dealuminated zeolite-Y with the silica alumina matrix, peptized alumina and kaolin clay. Detailed composition of each catalyst is given in Table-1. Accordingly, the present invention proxides a process for the preparation of novel FCC catalyst using modified crystalline alunino silicate zeolite especially Y type zeolite and silica-alumina sol based matrix which comprises: (i) preparing active silica-alumina matrix (sol) by mixing the calculated amount of sodium silicate and aluminium sulphate solutions so as to give silica-aluminium ratio of 80:20 at adjusted pH of 3.0, (ii) treating the kaolin clay with N/10 Hydrochloric acid at room temperature and t washing the treated clay free of chlorideion and drying at 110°C, (iii) preparing peptized alumina by known methods as herein described, (iv) exchanging NaY to NH4Y zeolite with an aqueous solution of ammonium salt such as NH4NO3, NH4CI, (NH4)2 SO4, (v) hydrothermal treatment of NH4Y zeolite in the presence of 100% steam in the temperature range of 380- 750°C for the durtaion of 1 to 10 hours for achieving the level of dealumination in the range of 20-60%, (vi) treating the said zeolite obtained in step(v) with mineral acids to obtain modified zeoEte, (vii) dispersing the slurry of modified zeolite, kaolin clay and peptized alumina obtained in steps (vi),(ii) and (iii) respectively is silica-alumina sol obtained in step 1 at controlled pH of 3.0. (viii) allowing the catalyst slurry consisting of silica-alumina sol, zeolite, clay and peptized alumina to age for a period upto 16 Hrs, (ix) filtering and washing the gel obtainedin step (viii) with water, drying and calcining at a temperature in the range of 400 to 600°C. (x) loading the said calcined product obtained in step (ix),by a rare earth salt solution as herein described by ion exchange to have 2-3 wt% rare earth metal, (xi) drying the rare earth exchanged product obtained in step (x) for a period in the range of 2-4 hours at a temperature in the range of 80-150°C to obtain Fluid Catalytic Cracking (F.C.C) catalyst, (xii) calcining the said catalyst at a temperature in the range of 400-600°C for a period of 2-3 hours and sieving to get 100-200 mesh size particles of catalyst. The invention may be practiced as illustrated in the following examples which should not be considered to limit the scope of the present invention. Example -1 This example describes a process for the preparation of FCC catalyst using 20% dealuminated zeolite-Y having composition given in Table-1 designated as FCCA. In a typical procedure, sodium silicate solution washiluted with distilled to have 10% silica. (Table Removed) It was added to 6NH2S04 till the ph of the mix was 2.5-3.0. Required amount of the modified kaolin clay was added and stirred well at PH below 3.0. Then required amount of 20% dealuminated zeolite -Y was added and stirred well to disperse the zeolite at PH below 3.0. After mixing of zeolite, the peptized alumina was added and PH was ~3.2. Then finally required amount of Al2(S04)3 solution was added to give 80:20 silica to. alumina ratio based on sodium silicate taken. The final PH was adjested to 3.5 using NaOH solution. The slurry was aged for 16 hrs at 4 0-45°C. The aged slurry (now gelled) was dried in oven at 110°C for 24 hours. The dried mass was washed with DM water with 2-3 washings with 0.5% NH4N03 solution and finally with DM water. The washed mass was dried in oven at 110°C and finally calcined at 350°C for 2 hrs. The calcined mass was exchanged with La(N03)3 solution at 85°C for 2 hrs to exchange maximum 2-3% La+++. The mass was filtered, dried in oven at 110°C and finally calcined at 500°C for 2 hours. The catalyst so obtained was crushed and sieved to get 100-200 mesh size particles and designated as FCC-A. Example - 2 The procedure and compostition for the catalyst prepared in this example was exactly the same as in 1, except that modified zeolite used in catalyst formulation was 60% dealuminated and designated as FCC-B. Example - 3 This example illustrates the hydrothermal deactivation of catalyst in presence of 100% steam at the following reaction conditions : Temperature : 786 - 792°C Duration : 3-5 hours Example - 4 This example illustrates the thermal and hydrothermal stability of catalyst by measuring surface area, % crystallinity, unit cell size, acidity and acid strength distribution of both fresh and steamed catalyst samples to asses their thermal and hydrothermal stability, modification of acid strength as a result of hydrothermal degradation. The detailed physico-chemical characteristics of the catalyst samples presented in Table-2 indicate higher thermal and hydrothermal stability of catalysts. Table-2 HYDROTHERMAL STABILITY OF FCC CATALYSTS (Table Removed) F = Fresh Catajfst S = Steamed i.e. liydrothernially treated catalyst We Claim: 1. A process for the preparation of novel Fluid catalytic cracking (FCC) catalyst using modified crystalline molecular sieve especially Y typeeolite and silica-alumina matrix which comprises: (i) preparing active silica-alumina matrix (sol) by abing the calculated amount of sodium silicate and aluminium sulphate solutions so as to give silca aluminium ratio of 80:20 at adjusted pH of 3.0, (ii) treating the kaolin clay with N/10 hydrochloric acid at room temperature and washing the treated clay free of chloride ion and drying at 110°C, (iii) preparing peptized alumina by known methods as herein described, (iv) exchanging NaY to NH4 Y zeolite with an aqueous solution of ammonium salt such as NH4NO3, (v) hydrothermal treatment of NH4Y zeolite in the presince of 100% steam in the temperature range of 380- 750°C forthe duration of 1 to 10 hours for achiveing the level of dealumination in the range of 20-60%, (vi) treating the said zeolite obtained in step (v) with singral acids to obtain modified zeolite, (vii) dispersing the slurry of modified zeolite, kaolinelay and peptized alurnina obtained in steps (vi),(ii) and (iii) respectively in silica-alumina sol obtained instep {i) at controlled pH of 3.0. (viii) allowing the catalyst slurry consisting of silica-alumina sol, zeolite, clay and peptized alumina to age for a period upto 16 Hrs to obtiangel, (ix) filtering and washing the gel obtained in step (viii) with water, drying and calcining at a temperature in the range of 400 to 600°C, (x) loading the said calcined product obtained in step (ix) by a rare earth salt solution as herein described by ion exchange to have 2-3 wt% rare eath metal, (xi) drying the rare earth exchanged product obtaianshis step (x) for a period in the range of 2,4 hours at a temperature in the range of 80-150°C to obtain Fuid Catalytic Cracking (FCC) catalyst, (xii) calcining the said catalyst at a temperature in the range of 400-600°C for a period of 2-3 hours and sieving to get 100-200 mesh size particles of catalyst 2. A process as claimed in claim 1 wherein the exchage of NaY zeolite to the NH4Y zeolite is affected by treatment with aqueous solution of ammonium salt of strength ranging from 1-3 N at a temperature in therangeof70-100°C. 3. A process as claimed in claims 1 and 2 wherein the ammonium salt such as sulphate or nitrate, preferably ammonium nitrate is used. 4. A process as claimed in claim 3 wherein in the concerrtation of the ammormim salt solution is adjusted to provide 2-6 equivalents of the cation per equivalent of total base exchange capacity. 5. A process as claimed in claims 1 to 4 wherein in step (vi) mineral acid such as HCL, HNO3 used to further enhance the crystallinity and the pore size of the zeolite Y and reducing sodium content to less than0.1%. 6. A process as claimed in clais l-5 where in the catalysts. 7. A process for the preparation of novel fluid catalytionratking (FCC) catalyst using modified crystalline molecular sieve and silica- alumina matrix as here in desecribed with reference to the examples.

Full Text

This invention relates to the process for the preparation of novel fluid catalytic cracking (FCC) catalyst using modified crystalline molecular sieve and silica- alumina matrix. In particular, the invention relates to a process for the preparation of novel FCC catalyst using modified zeolite with different degree of dealumination and silica-alumina matrix. The invention more specifically relates to a process for the preparation of novel FCC catalyst by dispersing modified zeolite in silica-alumina active matrix with improved hydrothermal stability and adequate catalytic and physical properties.
FCC catalyst is composed of zeolite and matrix. The zeolite is responsible for the bulk of the catalytic activity. The component referred as matrix fulfils both physical and catalytic functions. One of the major function of the matrix is to bind the zeolite particles together in micro spheroidal catalyst particles, hard enough to survive inter particle and reactor wall collisions. The presence of large (> 20A°) pores in the matrix allows it to serve as a diffusion medium for feed stock molecules and cracked products.
Dealuminated zeolite-Y is preferably used in FCC catalyst formulations, as dealumination of zeolite-Y leads to decrease in unit cell size (UCS), increases silica to alumina ratio which in turn increases the hydrothermal stability of the zeolite. As the degree of dealuination increases the total acidity decreases but the percentage of strong acid sites increases and sites\become isolated due to which H-transfer reaction occuring during
catalytic cracking reaction is suppressed and coke formation is reduced. Mesoporosity created by dealumination of zeolite-Y in conjunction with active matrix having larger pores, facilitate the diffusion of larger molecules present in the heavier fractions of the oil having higher molecular weight used as the FCC feed stock.
FCC catalyst prepared by dispersing dealuminated zeolite in silica-alumina gel matrix is known to have low Apparant Bulk Density (ABD) and poor attrition resistance due to low solid content of catalyst slurry at pumpability of spray dryer. The matrix prepared by amulinium chloro-hydrate based alumina sol is associated with highly viscous catalyst slurry which makes the pumpable characteristics of catalyst slurry very inferior, lower surface area and catalytic activity.
The matrix prepared by the process of the present invention based on silica-alumina sol fratrix controlling the pH of the medium at 3 or below to avoid gelation at the time of mixing the different ingredients results in improved hydrothermal stability. Ageing the silica-alumina sol after addition of other ingredients to convert it into gel result s in better binding strength of catalyst particles and. also catalytic properties due to stronger interaction of silica-alumina bond to generate appropriate acidity required for the catalytic cracking reaction. Use of optimum silica-alumina ratio (80:20) to maximise protonic acidity also improves the coke selectivity of the catalyst.
The objective of the present invention is therefore, to provide an improved process for the preparation of FCC catalyst with improved hydrothermal stability, physical and catalytic properties.
In each cycle of FCC operation, the catalyst is continuously deactivated by hydrothermal degradation as a result of dealumination of zeolite resulting in loss of activity. To compensate for the loss in aotivity, a part of the deactivated catalyst is replaced by the fresh catalyst to maintain the original activity of the catalyst. FCC catalyst having an adequate thermal and hydrothermal stability infers that it will have a high retention of surface area, zeolite crystallinity and acidity and thus the fresh catalyst addition rate will be reduced which will greatly affect the over all economics of the FCC operation.
The objective of the present invention is therefore, to provide a process for the preparation of novel FCC catalyst with improved thermal and hydrothermal stability.
In carryingout the present invention, as a result of extensive investigations carried out by us, two FCC catalysts were prepared using 20 and 60% dealuminated zeolite-Y with the silica alumina matrix, peptized alumina and kaolin clay. Detailed composition of each catalyst is given in Table-1.
Accordingly, the present invention proxides a process for the preparation of novel FCC catalyst using modified crystalline alunino silicate zeolite especially Y type zeolite and silica-alumina sol based matrix which comprises: (i) preparing active silica-alumina matrix (sol) by mixing the calculated amount of
sodium silicate and aluminium sulphate solutions so as to give silica-aluminium
ratio of 80:20 at adjusted pH of 3.0,
(ii) treating the kaolin clay with N/10 Hydrochloric acid at room temperature and
t
washing the treated clay free of chlorideion and drying at 110°C, (iii) preparing peptized alumina by known methods as herein described, (iv) exchanging NaY to NH4Y zeolite with an aqueous solution of ammonium salt such
as NH4NO3, NH4CI, (NH4)2 SO4, (v) hydrothermal treatment of NH4Y zeolite in the presence of 100% steam in the
temperature range of 380- 750°C for the durtaion of 1 to 10 hours for achieving the level
of dealumination in the range of 20-60%,
(vi) treating the said zeolite obtained in step(v) with mineral acids to obtain modified
zeoEte, (vii) dispersing the slurry of modified zeolite, kaolin clay and peptized alumina obtained
in steps (vi),(ii) and (iii) respectively is silica-alumina sol obtained in step 1 at
controlled pH of 3.0.
(viii) allowing the catalyst slurry consisting of silica-alumina sol, zeolite, clay and peptized alumina to age for a period upto 16 Hrs,
(ix) filtering and washing the gel obtainedin step (viii) with water, drying and calcining at a temperature in the range of 400 to 600°C.
(x) loading the said calcined product obtained in step (ix),by a rare earth salt solution as herein described by ion exchange to have 2-3 wt% rare earth metal,
(xi) drying the rare earth exchanged product obtained in step (x) for a period in the range of 2-4 hours at a temperature in the range of 80-150°C to obtain Fluid Catalytic Cracking (F.C.C) catalyst,
(xii) calcining the said catalyst at a temperature in the range of 400-600°C for a period of 2-3 hours and sieving to get 100-200 mesh size particles of catalyst.
The invention may be practiced as illustrated in the following examples which should not be considered to limit the scope of the present invention.
Example -1
This example describes a process for the preparation of FCC catalyst using 20% dealuminated zeolite-Y having composition given in Table-1 designated as FCCA. In a typical procedure, sodium silicate solution washiluted with distilled to have 10% silica.
(Table Removed)
It was added to 6NH2S04 till the ph of the mix was 2.5-3.0. Required amount of the modified kaolin clay was added and stirred well at PH below 3.0. Then required amount of 20% dealuminated zeolite -Y was added and stirred well to disperse the zeolite at PH below 3.0. After mixing of zeolite, the peptized alumina was added and PH was ~3.2. Then finally required amount of Al2(S04)3 solution was added to give 80:20 silica to. alumina ratio based on sodium silicate taken. The final PH was adjested to 3.5 using NaOH solution. The slurry was aged for 16 hrs at 4 0-45°C. The aged slurry (now gelled) was dried in oven at 110°C for 24 hours. The dried mass was washed with DM water with 2-3 washings with 0.5% NH4N03 solution and finally with DM water. The washed mass was dried in oven at 110°C and finally calcined at 350°C for 2 hrs. The calcined mass was exchanged with La(N03)3 solution at
85°C for 2 hrs to exchange maximum 2-3% La+++. The mass was filtered, dried in oven at 110°C and finally calcined at 500°C for 2 hours. The catalyst so obtained was crushed and sieved to get 100-200 mesh size particles and designated as FCC-A.
Example - 2
The procedure and compostition for the catalyst prepared in this example was exactly the same as in 1, except that modified zeolite used in catalyst formulation was 60% dealuminated and designated as FCC-B.
Example - 3
This example illustrates the hydrothermal deactivation of catalyst in presence of 100% steam at the following reaction conditions :
Temperature : 786 - 792°C Duration : 3-5 hours
Example - 4
This example illustrates the thermal and hydrothermal stability of catalyst by measuring surface area, % crystallinity, unit cell size, acidity and acid strength distribution of both fresh and steamed catalyst samples to asses their thermal and hydrothermal stability, modification of acid strength as a result of hydrothermal degradation. The detailed physico-chemical characteristics of the catalyst samples presented in Table-2 indicate higher thermal and hydrothermal stability of
catalysts.
Table-2 HYDROTHERMAL STABILITY OF FCC CATALYSTS
(Table Removed)
F = Fresh Catajfst
S = Steamed i.e. liydrothernially treated catalyst

We Claim:
1. A process for the preparation of novel Fluid catalytic cracking (FCC) catalyst using modified
crystalline molecular sieve especially Y typeeolite and silica-alumina matrix which comprises: (i) preparing active silica-alumina matrix (sol) by abing the calculated amount of sodium silicate and
aluminium sulphate solutions so as to give silca aluminium ratio of 80:20 at adjusted pH of 3.0, (ii) treating the kaolin clay with N/10 hydrochloric acid at room temperature and washing the treated
clay free of chloride ion and drying at 110°C, (iii) preparing peptized alumina by known methods as herein described, (iv) exchanging NaY to NH4 Y zeolite with an aqueous solution of ammonium salt such as NH4NO3,
(v) hydrothermal treatment of NH4Y zeolite in the presince of 100% steam in the temperature range of 380-
750°C forthe duration of 1 to 10 hours for achiveing the level of dealumination in the range of 20-60%, (vi) treating the said zeolite obtained in step (v) with singral acids to obtain modified zeolite, (vii) dispersing the slurry of modified zeolite, kaolinelay and peptized alurnina obtained in steps (vi),(ii) and
(iii) respectively in silica-alumina sol obtained instep {i) at controlled pH of 3.0. (viii) allowing the catalyst slurry consisting of silica-alumina sol, zeolite, clay and peptized
alumina to age for a period upto 16 Hrs to obtiangel, (ix) filtering and washing the gel obtained in step (viii) with water, drying and calcining at a
temperature in the range of 400 to 600°C, (x) loading the said calcined product obtained in step (ix) by a rare earth salt solution as herein
described by ion exchange to have 2-3 wt% rare eath metal, (xi) drying the rare earth exchanged product obtaianshis step (x) for a period in the range of 2,4 hours
at a temperature in the range of 80-150°C to obtain Fuid Catalytic Cracking (FCC) catalyst, (xii) calcining the said catalyst at a temperature in the range of 400-600°C for a period of 2-3 hours and sieving to get 100-200 mesh size particles of catalyst
2. A process as claimed in claim 1 wherein the exchage of NaY zeolite to the NH4Y zeolite is affected by
treatment with aqueous solution of ammonium salt of strength ranging from 1-3 N at a temperature in therangeof70-100°C.
3. A process as claimed in claims 1 and 2 wherein the ammonium salt such as sulphate or nitrate, preferably
ammonium nitrate is used.
4. A process as claimed in claim 3 wherein in the concerrtation of the ammormim salt solution is adjusted to
provide 2-6 equivalents of the cation per equivalent of total base exchange capacity.
5. A process as claimed in claims 1 to 4 wherein in step (vi) mineral acid such as HCL, HNO3 used to further enhance the crystallinity and the pore size of the zeolite Y and reducing sodium content to less than0.1%.
6. A process as claimed in clais l-5 where in the catalysts.
7. A process for the preparation of novel fluid catalytionratking (FCC) catalyst using modified crystalline
molecular sieve and silica- alumina matrix as here in desecribed with reference to the examples.

Documents:

742-del-1998-abstract.pdf

742-del-1998-claims.pdf

742-del-1998-complete specification (granted).pdf

742-del-1998-correspondence-others.pdf

742-del-1998-correspondence-po.pdf

742-del-1998-description (complete).pdf

742-del-1998-form-1.pdf

742-del-1998-form-19.pdf

742-del-1998-form-2.pdf

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Patent Number

194836

Indian Patent Application Number

742/DEL/1998

PG Journal Number

49/2004

Publication Date

04-Dec-2004

Grant Date

03-Mar-2006

Date of Filing

24-Mar-1998

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG NEW DELHI-110001, INDIA

Inventors:

#	Inventor's Name	Inventor's Address
1	RAGHUNATH PRASAD MALHOTRA	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
2	SADANAND DATTATREYA PHATAK	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
3	TURUGA SUNDARA RAMA PRASADA RAO	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
4	UMA SHANKAR	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
5	SURENDRANATH SURESH	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
6	MOOLCHAND	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
7	DAYAL SINGH RAWAT	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
8	VIJAY SINGH DANGWAL	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
9	NIRMALYA RAY	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
10	JAI KRISHNA GUPTA	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA
11	ANAND SINGH	INDIAN INSTITUTE OF PETROLEUM, DEHRADUN-248005, INDIA

PCT International Classification Number

B01J 29/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA