Manufacturing process for HFO-1234ze

US9255046B2 · US · B2

Patent metadata
FieldValue
Publication numberUS-9255046-B2
Application numberUS-12504508-A
CountryUS
Kind codeB2
Filing dateMay 21, 2008
Priority dateJul 25, 2003
Publication dateFeb 9, 2016
Grant dateFeb 9, 2016

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  5. First independent claim

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Abstract

Official abstract text for this publication.

Disclosed is a method for forming HFO-1234ze, and for forming compositions comprising HFO-1234ze, by (a) converting, preferably by dehydrofluorination, pentafluorpropane (HFC-245), preferably 1,1,1,3,3-pentafluorpropane (HFC-245fa), preferably by contact with a caustic solution, to a reaction product comprising cis-HFO-1234ze and trans-HFO-1234ze; and (b) contacting at least a portion, preferably substantially portion, and in certain embodiments substantially all of said reaction product with at least one isomerization catalyst to convert at least a portion, and preferably at least a substantial portion, of cis-HFO-1234ze in said reaction product to trans-HFO-1234ze.

First claim

Opening claim text (preview).

What is claimed is: 1. A process for the manufacture of a composition comprising trans-1,3,3,3 tetrafluoropropene (transHFO-1234ze) comprising: a) converting 1,1,1,3,3-pentafluoropropane to a reaction product comprising cis-1,3,3,3 tetrafluoropropene (cis-HFO-1234ze) and trans-HFO-1234ze; b) producing a feed stream comprising at least a portion of said cis-HFO-1234ze and said trans-HFO-1234ze from the reaction product of said converting step (a), wherein the amount of cis-HFO-1234ze in said feed stream is at least about 5% based on the total of HFO-1234ze in said feed stream; c) introducing said feed stream to an isomerization reactor having catalytic reaction conditions effective to convert at least about 70% of said cis-1,3,3,3 tetrafluoropropene in said feed stream, said conditions comprising exposing at least a portion of said cis-1,3,3,3 tetrafluoropropene in said feed stream to a metal based catalyst selected from the group consisting of halogenated metal oxides, Lewis acid metal halides, zero-valent metals, and combinations of these, at a temperature between about 50° C. and less than 200° C.; and (d) withdrawing from said isomerization reactor a reaction product having a selectivity to trans-1,3,3,3-tetrafluoropropene of at least 80%. 2. The process of claim 1 wherein the metal component of said halogenated metal oxide is selected from the group consisting of: (1) transition metals having an atomic number from about 21 to about 57, (2) metals from Group IIIA having an atomic number of from about 13 to about 81, (3) metals from Group VA having an atomic number of from about 51 to about 83, (4), rare earth metals such as cerium, (5) alkali metals from Group IA having an atomic number of from about 3 to about 37, (6) alkali earth metals from Group IIA having an atomic number of from about 12 to about 56, and (7) combinations of any two or more of them. 3. The process of claim 1 wherein the metal component of said Lewis acid metal halides is selected from the group consisting of: (1) transition metals having an atomic number from about 21 to about 57, (2) metals from Group IIIA having an atomic number of from about 13 to about 81, (3) metals from Group VA having an atomic number of from about 51 to about 83, (4), rare earth metals such as cerium, (5) alkali metals from Group IA having an atomic number of from about 3 to about 37, (6) alkali earth metals from Group IIA having an atomic number of from about 12 to about 56, and (7) combinations of any two or more of them. 4. The process of claim 1 wherein when said catalyst comprises a metal from group VIII or IB, and wherein said metal is present in a form in which its oxidation state is zero. 5. The process of claim 1 wherein said feed stream introduced in accordance with step (c) comprises at least about 10% by weight of cis-1,3,3,3 tetrafluoropropene based on the total of HFO-1234ze in said feed stream. 6. The process of claim 1 wherein said feed stream introduced in accordance with step (c) comprises at least about 15% by weight of cis-1,3,3,3 tetrafluoropropene based on the total of HFO-1234ze in said feed stream. 7. The process of claim 6 wherein said feed stream further comprises un-reacted halogenated propanes. 8. The process of claim 1 wherein said converting step (a) is carried out under conditions effective to convert at least about 70% of the HFC-245. 9. The process of claim 8 wherein said reaction conditions in step (c) are effective to convert at least about 90% of the cis-HFO-1234ze. 10. The process of claim 8 wherein said reaction conditions in step (c) are effective to convert at least about 95% of the cis-HFO-1234ze and to achieve a selectivity to the trans-HFO-1234ze of at least about 98%. 11. The process of claim 1 wherein said converting step (a) comprises a liquid phase reaction. 12. The process of claim 1 wherein said converting step (a) comprises reacting said HFC-245fa with at least one material selected from the group consisting of potassium hydroxide (KOH), sodium hydroxide (NaOH), Ca(OH)2, CaO, and combinations of these. 13. The process of claim 1 wherein said converting step (a) comprises reacting said HFC-245fa with at least one dehydrofluorinating agent comprising potassium hydroxide (KOH). 14. The process of claim 13 wherein said potassium hydroxide (KOH) is present in the form an aqueous solution. 15. The process of claim 1 wherein said converting step (a) is carried out at a temperature of from about 20° C. to about 100° C. 16. The process of claim 1 wherein said converting step (a) is carried out at a temperature of from about 30° C. to about 90° C. 17. The process of claim 16 wherein the metal component of said halogenated metal oxide is selected from the group consisting of: (1) transition metals having an atomic number from about 21 to about 57, (2) metals from Group IIIA having an atomic number of from about 13 to about 81, (3) metals from Group VA having an atomic number of from about 51 to about 83, (4), rare earth metals such as cerium, (5) alkali metals from Group IA having an atomic number of from about 3 to about 37, (6) alkali earth metals from Group IIA having an atomic number of from about 12 to about 56, and (7) combinations of any two or more of them. 18. The process of claim 1 wherein the metal component of said Lewis acid metal halides is selected from the group consisting of: (1) transition metals having an atomic number from about 21 to about 57, (2) metals from Group IIIA having an atomic number of from about 13 to about 81, (3) metals from Group VA having an atomic number of from about 51 to about 83, (4), rare earth metals such as cerium, (5) alkali metals from Group IA having an atomic number of from about 3 to about 37, (6) alkali earth metals from Group IIA having an atomic number of from about 12 to about 56, and (7) combinations of any two or more of them. 19. The process of claim 1 wherein when said catalyst comprises a metal from group VIII or IB, and wherein said metal is present in a form in which its oxidation state is zero.

Assignees

Inventors

Classifications

  • C07C17/25Primary

    by splitting-off hydrogen halides from halogenated hydrocarbons · CPC title

  • by isomerisation · CPC title

  • containing fluorine · CPC title

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What does patent US9255046B2 cover?
Disclosed is a method for forming HFO-1234ze, and for forming compositions comprising HFO-1234ze, by (a) converting, preferably by dehydrofluorination, pentafluorpropane (HFC-245), preferably 1,1,1,3,3-pentafluorpropane (HFC-245fa), preferably by contact with a caustic solution, to a reaction product comprising cis-HFO-1234ze and trans-HFO-1234ze; and (b) contacting at least a portion, preferab…
Who is the assignee on this patent?
Cottrell Stephen A, Tung Hsueh Sung, Wang Haiyou, and 3 more
What technology area does this patent fall under?
Primary CPC classification C07C17/25. Mapped technology areas include Chemistry & Metallurgy.
When was this patent published?
Publication date Tue Feb 09 2016 00:00:00 GMT+0000 (Coordinated Universal Time) (B2). Legal status and post-grant events are not shown on this page.
What related patents are in patentsdb?
We list 8 related publications on this page (citations in our corpus or others sharing the same primary CPC).