FLUORINE REMOVAL FROM ANTIMONY FLUOROHALIDE CATALYST USING CHLOROCARBONS
A method of chlorinating an antimony fluorohalide catalyst is disclosed. In one embodiment the method comprises contacting an antimony fluorohalide catalyst that contains one or more fluorines with a regenerating agent selected from 2-chloro-3,3,3-trifluoropropene (1233xf), 1,1,1,3-tetrachloropropane (250fb), 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), and combinations of 1233xf, 250fb, and 244bb, under conditions effective to exchange at least one fluorine in the antimony fluorohalide catalyst with chlorine. The method can be used to regenerate spent antimony fluorohalide catalyst, for example regenerating SbCl 5 from SbF 5 .
1 . A process to prepare 2-chloro-1,1,1,2-tetrafluoropropane (244bb) comprising contacting 2-chloro-3,3,3,-trifluoropropene (1233xf) with HF and a chlorine-containing antimony catalyst under conditions effective to produce a composition that comprises 244bb, wherein the chlorine-containing antimony catalyst is prepared by treating a spent antimony fluorohalide catalyst comprising:
(i) SbF n X 5-n , wherein n is an integer of 1 to 5, and X is a halogen other than fluorine,
(ii) SbF m X′ 3-m , wherein m is an integer of 1 to 3, and X′ is a halogen other than fluorine, or
(iii) mixtures of (i) and (ii),
with a regenerating agent selected from 2-chloro-3,3,3-trifluoropropene (1233xf), 1,1,1,3-tetrachloropropane (250fb), 2-chloro-1,1,1,2-tetrafluoropropane (244bb), and combinations of two or more of 1233xf, 250fb, and 244bb, under conditions effective to produce the chlorine-containing antimony catalyst from the spent antimony fluorohalide catalyst.
2 . The process of claim 1 , wherein the chlorine-containing antimony catalyst comprises SbCl 3 or SbCl 5 .
3 . The process of claim 1 , wherein the chlorine-containing antimony catalyst comprises SbCl 3 and at least one of SbFCl 2 and SbF 2 Cl.
4 . The process of claim 1 , wherein the chlorine-containing antimony catalyst comprises SbCl 5 and at least one of SbFCl 4 , SbF 2 Cl 3 , SbF 3 Cl 2 , and SbF 4 Cl.
5 . A process to prepare 2,3,3,3-tetrafluoropropene (1234yf) comprising:
a) providing a starting composition comprising at least one compound having the structure of Formula I:
CX″ 2 ═CCl—CH 2 X″ (Formula I)
wherein each X″ is independently selected from F, Cl, Br, and I, provided that at least one of X″ is not F;
b) contacting said starting composition with HF under conditions effective to produce a first intermediate composition comprising 2-chloro-3,3,3-trifluoropropene (1233xf);
c) contacting said first intermediate composition comprising 1233xf with HF and a chlorine-containing antimony catalyst under conditions effective to produce a second intermediate composition comprising 244bb; and
d) dehydrochlorinating at least a portion of said 244bb to produce a reaction product comprising 1234yf, wherein the chlorine-containing antimony catalyst is prepared by treating a spent antimony fluorohalide catalyst comprising:
(i) SbF n X 5-n , wherein n is an integer of 1 to 5, and X is a halogen other than fluorine,
(ii) SbF m X′ 3-m , wherein m is an integer of 1 to 3, and X′ is a halogen other than fluorine, or
(iii) mixtures of (i) and (ii),
with a regenerating agent selected from 2-chloro-3,3,3-trifluoropropene (1233xf), 1,1,1,3-tetrachloropropane (250fb), 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), and combinations of two or more of 1233xf, 250fb, and 244bb, under conditions effective to produce the chlorine-containing antimony catalyst from the spent antimony fluorohalide catalyst.
6 . The process of claim 5 , wherein the starting composition comprises 1,1,2,3-tetrachloropropene (TCP).
7 . The process of claim 5 , wherein the chlorine-containing antimony catalyst comprises SbCl 3 or SbCl 5 .
8 . The process of claim 5 , wherein the chlorine-containing antimony catalyst comprises SbCl 3 and at least one of SbFCl 2 and SbF 2 Cl.
9 . The process of claim 5 , wherein the chlorine-containing antimony catalyst comprises SbCl 5 and at least one of SbFCl 4 , SbF 2 Cl 3 , SbF 3 Cl 2 , and SbF 4 Cl.
10 . A process to prepare 2,3,3,3-tetrafluoropropene (1234yf) comprising:
a) providing a starting composition comprising at least one compound having the structure of Formula III:
CX″ 3 —CHCl—CH 2 X″ (Formula III)
wherein each X″ is independently selected from F, Cl, Br, and I, provided that at least one of X″ is not F;
b) dehydrohalogenating said starting composition under conditions effective to produce a first intermediate composition comprising 2-chloro-3,3,3-trifluoropropene (1233xf);
c) contacting said first intermediate composition comprising 1233xf with HF and a chlorine-containing antimony catalyst under conditions effective to produce a second intermediate composition comprising 244bb; and
d) dehydrochlorinating at least a portion of said 244bb to produce a reaction product comprising 1234yf, wherein the chlorine-containing antimony catalyst is prepared by treating a spent antimony fluorohalide catalyst comprising:
(i) SbF n X 5-n , wherein n is an integer of 1 to 5, and X is a halogen other than fluorine,
(ii) SbF m X′ 3-m , wherein m is an integer of 1 to 3, and X′ is a halogen other than fluorine, or
(iii) mixtures of (i) and (ii),
with a regenerating agent selected from 2-chloro-3,3,3-trifluoropropene (1233xf), 1,1,1,3-tetrachloropropane (250fb), 2-chloro-1,1,1,2-tetrafluoropropane (HCFC-244bb), and combinations of two or more of 1233xf, 250fb, and 244bb, under conditions effective to produce the chlorine-containing antimony catalyst from the spent antimony fluorohalide catalyst.
11 . The process of claim 10 , wherein the starting composition comprises 1,2-dichloro-3,3,3,-trifluoropropane (243db).
12 . The process of claim 10 , wherein the chlorine-containing antimony catalyst comprises SbCl 3 or SbCl 5 .
13 . The process of claim 10 , wherein the chlorine-containing antimony catalyst comprises SbCl 3 and at least one of SbFCl 2 and SbF 2 Cl.
14 . The process of claim 10 , wherein the chlorine-containing antimony catalyst comprises SbCl 5 and at least one of SbFCl 4 , SbF 2 Cl 3 , SbF 3 Cl 2 , and SbF 4 Cl.