Claims
- 1. A process for converting C.sub.3 aliphatic hydrocarbon feed to produce primarily C.sub.4.sup.+ aliphatic hydrocarbons comprising contacting a C.sub.3 feed containing propane and about 10% to 40% by weight mono-olefin with an acidic shape selective medium pore zeolite catalyst having a Constraint Index of 1 to 12 at a temperature of about 200.degree. to 400.degree. C. and a pressure above about 3400 kPa under reaction conditions to convert at least 10% of the propane; and
- recovering a product rich in C.sub.4.sup.+ aliphatic hydrocarbons and not more than 10 wt. % total methane and ethane.
- 2. A process for preparing a hydrocarbon mixture comprising primarily C.sub.4.sup.+ aliphatic hydrocarbons while minimizing the formation of methane and ethane, the process consisting essentially of:
- contacting in a fixed bed reaction zone under conversion conditions a mixed feed comprising about 60 wt. % to 90 wt. % propane and a mono-olefin or olefin precursor with a porous crystalline acidic metallosilicate zeolite catalyst having an acid cracking activity (alpha value) greater than 100, to convert at least 10% of the propane; and
- withdrawing from the reaction zone a hydrocarbon product containing no more than 10 wt. % cracking products consisting of methane and ethane.
- 3. A process according to claim 2 wherein the conversion conditions comprise a temperature of about 200.degree. C. to 370.degree. C., a pressure above about 3400 kPa, a weight hourly space velocity of about 0.1 to 100, and in the essential absence of hydrogen.
- 4. A process according to claim 2 wherein unconverted propane is separated from the hydrocarbon product and recycled to the fixed bed reaction zone.
- 5. A process according to claim 2 wherein the catalyst comprises aluminosilicate H-ZSM-5 zeolite free of hydrogenation-dehydrogenation components.
- 6. A process according to claim 2 wherein the olefin comprises propylene.
- 7. A process according to claim 2 wherein the mixed feed comprises about 80 wt. % propane and 20 wt. % propylene.
- 8. In a process for the production of n-butane, isobutane, and primarily C.sub.5.sup.+ aliphatic hydrocarbons by contacting a propane feed in the essential absence of added hydrogen and at a pressure of at least about 3400 kPa with a catalyst comprising a crystalline zeolite having a silica-to-alumina ratio of at least 12 and a Constraint Index of 1 to 12 under a combination of conditions of temperature, pressure, and WHSV effective to convert up to about 25% by weight of the propane feed, the improvement comprising:
- adding to the propane feed from about 10% to 20% by weight of at least one C.sub.2 -C.sub.16 mono-olefin, thereby increasing the reaction rate of the propane feed; and
- obtaining a product comprising butanes and no more than 10% by weight total methane and ethane.
- 9. A process according to claim 8 wherein the mono-olefin is a C.sub.2 -C.sub.4 hydrocarbon and the product contains at least 10 wt. % C.sub.5.sup.+ aliphatic hydrocarbons, based on conversion of the propane alone.
- 10. A process according to claim 8 wherein the product contains no more than 40 wt. % aromatics.
- 11. A process according to claim 8 wherein the product is fractionated to obtain isobutane, a hydrocarbon stream consisting essentially of unreacted propane, a C.sub.2.sup.- hydrocarbon stream, and a C.sub.5.sup.+ hydrocarbon stream.
- 12. A process according to claim 11 wherein the stream consisting essentially of unreacted propane is recycled for contact with the crystalline zeolite catalyst.
- 13. A process for preparing a hydrocarbon mixture comprising C.sub.4.sup.+ aliphatic hydrocarbons while minimizing the formation of methane and ethane, the process consisting essentially of:
- contacting in a fixed bed reaction zone under conversion conditions a mixed feed comprising propane and a mono-olefin or olefin precursor with a porous crystalline acidic metallosilicate zeolite catalyst having a Constraint Index of 1 to 12 and having an alpha value greater than 100, to convert at least 10 wt. % of the propane;
- withdrawing from the reaction zone a hydrocarbon product containing not more than 10 wt. % cracking products consisting of methane and ethane; and
- separating a hydrocarbon stream containing unreacted propane from the hydrocarbon product; and
- recycling the stream to be fixed bed reaction zone in an amount sufficient to maintain the mixed feed composition at about 60 wt. % to 90 wt. % propane.
- 14. A process according to claim 13 wherein the fixed bed reaction zone is maintained at a temperature of about 200.degree. C. to 400.degree. C. and a pressure of above about 3400 kPa.
- 15. A process according to claim 13 wherein the zeolite catalyst comprises a crystalline metallosilicate having the structure of ZSM-5.
- 16. A process according to claim 13 wherein the hydrocarbon product is further separated to obtain isobutane, a C.sub.2.sup.- hydrocarbon stream, and a C.sub.5.sup.+ hydrocarbon stream.
- 17. A process for catalytic conversion of an olefin-rich hydrocarbon feedstream containing propane comprising contacting the feedstream with an acid medium pore zeolite catalyst in a catalytic reaction zone to obtain a product containing C.sub.4.sup.+ aliphatic hydrocarbons;
- separating the product to obtain a first fraction rich in unreacted propane and a second fraction comprising C.sub.4.sup.+ aliphatic hydrocarbons;
- recycling the propane-rich first fraction for admixture with the olefin-rich hydrocarbon feedstream to obtain a composite feedstream comprising about 60-90 wt. % propane and about 10-40 wt. % olefin; and
- conducting the composite feedstream to the reaction zone for catalytic conversion.
- 18. A process according to claim 17 wherein the catalytic reaction zone is operated at a temperature of about 200.degree. C. to 400.degree. C. and the conversion reaction is conducted in the essential absence of added hydrogen.
- 19. A process according to claim 17 wherein the catalytic reaction zone contains an amount of acidic zeolite catalyst having the structure of ZSM-5 and effective to convert the composite feedstream to higher hydrocarbon products.
- 20. A process according to claim 17 wherein the catalytic reaction zone is operated at a pressure above about 3400 kPa.
- 21. A process according to claim 17 wherein the composite feedstream is catalytically converted to a hydrocarbon product containing at least 50 wt. % butanes and not more than 10 wt. % methane and ethane, based on conversion of propane alone.
- 22. A process according to claim 17 wherein at least 10 wt. % of the propane in the composite feedstream is converted to product.
- 23. A process according to claim 8 wherein the WHSV is about 0.1 to 100 and the temperature is below about 370.degree. C.
REFERENCE TO COPENDING APPLICATION
This application is a continuation-in-part of U.S. patent application Ser. No. 845,284, filed Mar. 28, 1986, now U.S. Pat. No. 4,686,316, incorporated herein by reference.
US Referenced Citations (12)
Non-Patent Literature Citations (1)
Entry |
Engelen et al, Applied Catalysis, 19, 153-163 (1985). |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
845284 |
Mar 1986 |
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