Title of Invention	"A SULPHUR -SORPTIVE MEMBRANE AND A METHOD FOR SEPARATION OF SULPHUR COMPOUNDS FROM LIQUID HYDROCARBONS"
Abstract	The present invention relates to a sulphur-sorptive membrane for separating sulphur compounds from a liquid hydrocarbon mixture such as gasoline, diesel, kerosene, aviation turbine fuel and other hydrocarbon fuels. The membrane is made of a co-polymer, wherein the monomers Hansen's three-dimensional solubility parameter is similar to that of the sulphur compound present in the hydrocarbon mixture. The membrane has a sulphur enrichment factor from about 2 to about 15. The present invention also relates to a process for separating sulphur compounds from a liquid hydrocarbon mixture using the membrane.

Title of Invention

"A SULPHUR -SORPTIVE MEMBRANE AND A METHOD FOR SEPARATION OF SULPHUR COMPOUNDS FROM LIQUID HYDROCARBONS"

Abstract

The present invention relates to a sulphur-sorptive membrane for separating sulphur compounds from a liquid hydrocarbon mixture such as gasoline, diesel, kerosene, aviation turbine fuel and other hydrocarbon fuels. The membrane is made of a co-polymer, wherein the monomers Hansen's three-dimensional solubility parameter is similar to that of the sulphur compound present in the hydrocarbon mixture. The membrane has a sulphur enrichment factor from about 2 to about 15. The present invention also relates to a process for separating sulphur compounds from a liquid hydrocarbon mixture using the membrane.

Full Text	A SULPHUR-SORPTIVE MEMBRANE AND A METHOD FOR SEPARATION OF SULPHUR COMPOUNDS FROM LIQUID HYDROCARBONS FIELD OF INVENTION The present invention relates to a sulphur-sorptive membrane and to a method for separating sulphur compound from a liquid hydrocarbon mixture using the membrane. BACKGROUND AND PRIOR ART New environmental regulations especially with respect to sulphur content in hydrocarbon products have led refiners to consider new technologies for the production of cleaner fuels. As the maximum allowable limit for the sulphur in hydrocarbon products shrinks due to tightening of government regulations, it is now necessary to find novel, less energy intensive processes as an alternative to conventional hydrotreating for sulphur removal. Hydrotreating entails high capital and operating costs and loss in octane number [US Pat. Appl.No.2002153284 (Lesemann et al.)]. Alternative processes to conventional hydrotreating are membrane technology, adsorption and catalytic distillation [US Pat. Appl. No.2002153284 (Lesemann et al.)]. Benefits of employing membrane technology are low capital and operating costs, low power consumption, ease of operation, ease of scale up and no octane loss. Some patents are available on the selective permeation of Sulphur compounds from the model hydrocarbon feed using membrane separation process. However, membranes that are more stable, and can sustain high selectivity for sulphur compounds at high vacuum and high temperature conditions successfully at an economically viable cost are needed. US Pat. No. 5,396,019 (Sartori et al.) describes the use of cross-linked fluorinated polyolefin membranes. US Pat. No.5,643,442 (Sweet et. al.) describes lowering of Sulphur compound content from hydrotreated distillate effluent feed using polyester-imide membrane. US Pat. Appl.No.20020153284 (Lesemann et al.) emphasizes on the selective separation of sulphur compounds like thiophene, thiophene derivatives, and mercaptans from FCC naphtha using polyamide membrane, polyurea urethane membrane, and polysilioxane membrane. Sulphur enrichment factors range from 2 to 20 depending upon the feed sulphur compound concentration. Sulphur content of the retentate stream can be lowered to the values prescribed using such membranes. US Pat. Appl. No. 20020139713A1 describes the use of Nanofilteration SR-90 (Filmtec Corporation, USA), Ultrafilteration G-10 (Osmonics Corporation, USA), and i Polysulfone SEP-0013 under perstraction mode to remove Sulphur compounds selectively from feed naphtha. Sulphur enrichment factor ranges from f to 13.1 and Sulphur content of retentate stream is reduced to less than 100 ppm. US Pat. Appl.No.20020139719 (Pinnau et al.) describes a method for removal of Sulphur compounds from light cracked naphtha employing hydrophilic, non-ionic membranes like polyvinylpyrrolidone and cellulose triacetate. In the process, Sulphur content of retentate stream is reduced to less than 300 ppm and Sulphur enrichment factors obtained range from 2 to 10. SUMMARY OF THE INVENTION The objects of the present invention are fulfilled by providing a membrane for separating sulphur compound from a liquid hydrocarbon mixture, wherein the membrane comprises of a co-polymer of at least two monomers selected from a group of monomer whose Hansen's three-dimensional solubility parameter is similar to that of sulphur compound present in the hydrocarbon mixture. Accordingly, the present invention relates to a sulphur-sorptive membrane and to a process for separating sulphur compounds from a liquid hydrocarbon mixture using the membrane. The membrane is cast from a co-polymer having a greater selectivity for the sulphur compounds than for the hydrocarbon mixture. The co-polymer can be synthesized from its monomers by conventionally known polymerization techniques such as emulsion polymerization. The preferred monomers are ones whose Hansen's three-dimensional solubility parameter is similar to that of the sulphur compound present in the hydrocarbon mixture. The preferred monomers include 2-hydroxy ethylmethacrylate, methylmethacrylate, methacrylic acid, acrylic acid, acrylonitrile, vinyl acetate, cellulose acetate and cellulose triacetate. The membrane thus designed has a sulphur enrichment factor from about 2 to about 15. The liquid hydrocarbon feed is preferably a conventional refinery hydrocarbon stream such as gasoline, diesel, kerosene, aviation turbine fuel and other hydrocarbon fuels. The content of sulphur compounds in the feed can be in the range of 30 to 3000 ppmwt and is preferably in the range of 50 to 1000 ppmwt. The sulphur compounds present are preferably thibphene, arylthiophenes, alkyl substituted arylthtophenes or We claim: 1. A membrane for separating sulphur compound from a liquid hydrocarbon mixture, wherein the membrane comprises of a co-polymer of at least two monomers selected from a group of monomers whose Hansen's three-dimensional solubility parameter is similar to that of sulphur compound present in the hydrocarbon mixture. 2. The membrane of claim 1, wherein the monomers are selected from the group consisting of 2-hydroxy ethylmethacrylate, methylmethacrylate, methacrylic acid, acrylic acid, acrylonitrile, vinyl acetate, cellulose acetate and cellulose triacetate. 3. The membrane of claim 1, wherein the weight percentage ratio of the first monomer to the second monomer is in the range 90-100:10-0. 4. The membrane of claim 1, wherein the first monomer is preferably acrylonitrile. 5. The membrane of claim 1, wherein the co-polymer is synthesized by emulsion polymerization method. 6. The membrane of claim 1, wherein the membrane is made by casting method. 7. The membrane of claim 1, wherein the sulphur compound present in the hydrocarbon mixture is selected from a group consisting of thiophene, arylthiophene, alkyl substituted arylthiophene or its derivative thereof. 8. The membrane of claim 1, wherein sulphur compound present in the hydrocarbon mixture is selected from a group consisting of thiophene, benzothiophene, dibenzothiophene and methyl substituted dibenzothiophene. 9. A method for separating sulphur compound from a liquid hydrocarbon mixture comprising of: contacting a liquid hydrocarbon mixture with a sulphur sorptive membrane, wherein said membrane is cast using a polymer or a co-polymer selected from a group of monomers is cast using a polymer or a co-polymer selected from a group of monomers whose Hansen's three-dimensional solubility is similar to that of sulphur compound present in the hydrocarbon mixture; selectively permeating said sulphur compound from said liquid hydrocarbon mixture through said membrane forming a sulphur-rich permeate and a sulphur-lean retentate; and retrieving said sulphur-rich permeate and a sulphur-lean retentate. 10. The method of claim 9, wherein the said hydrocarbon mixture has boiling range between 40 to 400°C and preferably between 40 to 200°C. 11. The method of claim 9, wherein the hydrocarbon mixture is selected from a group consisting of gasoline, diesel, kerosene, aviation turbine fuel and other hydrocarbon fuels. 12. The method of claim 9, wherein the sulphur compound present " in the hydrocarbon mixture is selected from a group consisting of thiophene, arylthiophene, alkyl substituted arylthiophene or its derivative thereof. 13. The method of claim 9, wherein the sulphur compound present in the hydrocarbon mixture is selected from a group consisting of thiophene, benzothiophenes, dibenzothiophenes and methyl substituted dibenzothiophenes. 14. The method of claim 9, wherein the sulphur compound present in the liquid hydrocarbon mixture is in the range of 30 to 3000 ppmwt and preferably in the range of 50 to 1000 ppmwt. 15. The method of claim 9, wherein the monomer is selected from the group comprising of 2- hydroxy ethylmethacrylate, methylmethacrylate, methacrylic acid, acrylonitrile, acrylic acid, vinyl acetate, cellulose acetate and cellulose triacetate. 16. The membrane of claim 9, wherein the first monomer is acrylonitrile. 17. The method of claim 9, wherein the polymer is synthesized by emulsion polymerization method. 18. The method of claim 9, wherein the weight percentage ratio of the first monomer: second monomer is in the range 90-100: 10-0. 19. The method of claim 9, wherein feed side pressure ranges from 1.0 to 20.0 atm and permeate side pressure from 0.4 to 1.0 atm. 20. The method of claim 9, wherein the said membrane has a sulphur enrichment factor from 2 to 15. 21. The method of claim 9, wherein the said sulphur compound is separated by pervaporation.

Full Text

A SULPHUR-SORPTIVE MEMBRANE AND A METHOD FOR SEPARATION OF SULPHUR COMPOUNDS FROM LIQUID HYDROCARBONS
FIELD OF INVENTION
The present invention relates to a sulphur-sorptive membrane and to a method for separating sulphur compound from a liquid hydrocarbon mixture using the membrane.
BACKGROUND AND PRIOR ART
New environmental regulations especially with respect to sulphur content in hydrocarbon products have led refiners to consider new technologies for the production of cleaner fuels. As the maximum allowable limit for the sulphur in hydrocarbon products shrinks due to tightening of government regulations, it is now necessary to find novel, less energy intensive processes as an alternative to conventional hydrotreating for sulphur removal. Hydrotreating entails high capital and operating costs and loss in octane number [US Pat. Appl.No.2002153284 (Lesemann et al.)].
Alternative processes to conventional hydrotreating are membrane technology, adsorption and catalytic distillation [US Pat. Appl. No.2002153284 (Lesemann et al.)]. Benefits of employing membrane technology are low capital and operating costs, low power consumption, ease of operation, ease of scale up and no octane loss. Some patents are available on the selective permeation of Sulphur compounds from the model hydrocarbon feed using membrane separation process. However, membranes that are more stable, and can sustain high selectivity for sulphur compounds at high vacuum and high temperature conditions successfully at an economically viable cost are needed.
US Pat. No. 5,396,019 (Sartori et al.) describes the use of cross-linked fluorinated polyolefin membranes. US Pat. No.5,643,442 (Sweet et. al.) describes lowering of Sulphur compound content from hydrotreated distillate effluent feed using polyester-imide membrane.
US Pat. Appl.No.20020153284 (Lesemann et al.) emphasizes on the selective separation of sulphur compounds like thiophene, thiophene derivatives, and mercaptans from FCC naphtha using polyamide membrane, polyurea urethane membrane, and polysilioxane membrane. Sulphur enrichment factors range from 2 to 20 depending upon the feed sulphur compound concentration. Sulphur content of the retentate stream can be lowered to the values prescribed using such membranes.

US Pat. Appl. No. 20020139713A1 describes the use of Nanofilteration SR-90
(Filmtec Corporation, USA), Ultrafilteration G-10 (Osmonics Corporation, USA), and
i Polysulfone SEP-0013 under perstraction mode to remove Sulphur compounds
selectively from feed naphtha. Sulphur enrichment factor ranges from f to 13.1 and
Sulphur content of retentate stream is reduced to less than 100 ppm.
US Pat. Appl.No.20020139719 (Pinnau et al.) describes a method for removal of
Sulphur compounds from light cracked naphtha employing hydrophilic, non-ionic
membranes like polyvinylpyrrolidone and cellulose triacetate. In the process, Sulphur
content of retentate stream is reduced to less than 300 ppm and Sulphur enrichment
factors obtained range from 2 to 10.
SUMMARY OF THE INVENTION
The objects of the present invention are fulfilled by providing a membrane for separating sulphur compound from a liquid hydrocarbon mixture, wherein the membrane comprises of a co-polymer of at least two monomers selected from a group of monomer whose Hansen's three-dimensional solubility parameter is similar to that of sulphur compound present in the hydrocarbon mixture.
Accordingly, the present invention relates to a sulphur-sorptive membrane and to a process for separating sulphur compounds from a liquid hydrocarbon mixture using the membrane. The membrane is cast from a co-polymer having a greater selectivity for the sulphur compounds than for the hydrocarbon mixture. The co-polymer can be synthesized from its monomers by conventionally known polymerization techniques such as emulsion polymerization. The preferred monomers are ones whose Hansen's three-dimensional solubility parameter is similar to that of the sulphur compound present in the hydrocarbon mixture. The preferred monomers include 2-hydroxy ethylmethacrylate, methylmethacrylate, methacrylic acid, acrylic acid, acrylonitrile, vinyl acetate, cellulose acetate and cellulose triacetate. The membrane thus designed has a sulphur enrichment factor from about 2 to about 15.
The liquid hydrocarbon feed is preferably a conventional refinery hydrocarbon stream such as gasoline, diesel, kerosene, aviation turbine fuel and other hydrocarbon fuels. The content of sulphur compounds in the feed can be in the range of 30 to 3000 ppmwt and is preferably in the range of 50 to 1000 ppmwt. The sulphur compounds present are preferably thibphene, arylthiophenes, alkyl substituted arylthtophenes or

We claim:
1. A membrane for separating sulphur compound from a liquid hydrocarbon mixture, wherein the membrane comprises of a co-polymer of at least two monomers selected from a group of monomers whose Hansen's three-dimensional solubility parameter is similar to that of sulphur compound present in the hydrocarbon mixture.
2. The membrane of claim 1, wherein the monomers are selected from the group consisting of 2-hydroxy ethylmethacrylate, methylmethacrylate, methacrylic acid, acrylic acid, acrylonitrile, vinyl acetate, cellulose acetate and cellulose triacetate.
3. The membrane of claim 1, wherein the weight percentage ratio of the first monomer to the second monomer is in the range 90-100:10-0.
4. The membrane of claim 1, wherein the first monomer is preferably acrylonitrile.
5. The membrane of claim 1, wherein the co-polymer is synthesized by emulsion polymerization method.
6. The membrane of claim 1, wherein the membrane is made by casting method.
7. The membrane of claim 1, wherein the sulphur compound present in the hydrocarbon mixture is selected from a group consisting of thiophene, arylthiophene, alkyl substituted arylthiophene or its derivative thereof.
8. The membrane of claim 1, wherein sulphur compound present in the hydrocarbon mixture is selected from a group consisting of thiophene, benzothiophene, dibenzothiophene and methyl substituted dibenzothiophene.
9. A method for separating sulphur compound from a liquid hydrocarbon mixture comprising of: contacting a liquid hydrocarbon mixture with a sulphur sorptive membrane, wherein said membrane is cast using a polymer or a co-polymer selected from a group of monomers is cast using a polymer or a co-polymer selected from a group of monomers whose Hansen's three-dimensional solubility is similar to that of sulphur compound present in the hydrocarbon mixture; selectively permeating said sulphur compound from said liquid hydrocarbon mixture through said membrane forming a sulphur-rich permeate and a sulphur-lean retentate; and retrieving said sulphur-rich permeate and a sulphur-lean retentate.
10. The method of claim 9, wherein the said hydrocarbon mixture has boiling range between 40 to 400°C and preferably between 40 to 200°C.
11. The method of claim 9, wherein the hydrocarbon mixture is selected from a group
consisting of gasoline, diesel, kerosene, aviation turbine fuel and other hydrocarbon fuels.
12. The method of claim 9, wherein the sulphur compound present " in the hydrocarbon
mixture is selected from a group consisting of thiophene, arylthiophene, alkyl substituted
arylthiophene or its derivative thereof.
13. The method of claim 9, wherein the sulphur compound present in the hydrocarbon mixture is selected from a group consisting of thiophene, benzothiophenes, dibenzothiophenes and methyl substituted dibenzothiophenes.
14. The method of claim 9, wherein the sulphur compound present in the liquid hydrocarbon mixture is in the range of 30 to 3000 ppmwt and preferably in the range of 50 to 1000
ppmwt.
15. The method of claim 9, wherein the monomer is selected from the group comprising of 2-
hydroxy ethylmethacrylate, methylmethacrylate, methacrylic acid, acrylonitrile, acrylic
acid, vinyl acetate, cellulose acetate and cellulose triacetate.
16. The membrane of claim 9, wherein the first monomer is acrylonitrile.
17. The method of claim 9, wherein the polymer is synthesized by emulsion polymerization
method.
18. The method of claim 9, wherein the weight percentage ratio of the first monomer: second
monomer is in the range 90-100: 10-0.
19. The method of claim 9, wherein feed side pressure ranges from 1.0 to 20.0 atm and
permeate side pressure from 0.4 to 1.0 atm.
20. The method of claim 9, wherein the said membrane has a sulphur enrichment factor from
2 to 15.
21. The method of claim 9, wherein the said sulphur compound is separated by pervaporation.

Documents:

1015-DEL-2005-Abstract-(01-03-2012).pdf

1015-del-2005-abstract.pdf

1015-del-2005-assignment.pdf

1015-DEL-2005-Claims-(01-03-2012).pdf

1015-DEL-2005-Correspondence Others-(01-03-2012).pdf

1015-DEL-2005-Correspondence Others-(16-02-2012).pdf

1015-del-2005-correspondence-others.pdf

1015-DEL-2005-Description (Complete)-(01-03-2012).pdf

1015-del-2005-description (provisional).pdf

1015-del-2005-drawings.pdf

1015-del-2005-form-1.pdf

1015-del-2005-form-18.pdf

1015-DEL-2005-Form-2-(01-03-2012).pdf

1015-del-2005-form-2.pdf

1015-del-2005-form-26.pdf

1015-del-2005-form-3.pdf

1015-del-2005-form-5.pdf

1015-DEL-2005-GPA-(16-02-2012).pdf

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Patent Number

252240

Indian Patent Application Number

1015/DEL/2005

PG Journal Number

18/2012

Publication Date

04-May-2012

Grant Date

02-May-2012

Date of Filing

25-Apr-2005

Name of Patentee

INDIAN OIL CORPORATION LTD.

Applicant Address

R&D CENTRE, SECTOR-13, FARIDABAD -121 007, HARYANA, INDIA

Inventors:

#	Inventor's Name	Inventor's Address
1	PORE ANAND SHARAD	UNIVERSITY INSTITUTE OF CHEMICAL TECHNOLOGY, UNIVERSITY OF MUMBAI, MUMBAI - 400019, INDIA
2	PANGARKAR VISHWAW GOVIND	UNIVERSITY INSTITUTE OF CHEMICAL TECHNOLOGY, UNIVERSITY OF MUMBAI, MUMBAI - 400019, INDIA
3	RAMAN NADUHATTY SELAI	INDIAN OIL CORPORATION, R&D CENTRE, SECTOR-13, FARIDABAD-121007, HARYANA, INDIA
4	SAYANNA ELTEPU	INDIAN OIL CORPORATION, R&D CENTRE, SECTOR-13, FARIDABAD-121007, HARYANA, INDIA
5	VERMA RAM PRAKASH	INDIAN OIL CORPORATION, R&D CENTRE, SECTOR-13, FARIDABAD-121007, HARYANA, INDIA

PCT International Classification Number

B01D61/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA