Claims
- 1. A process of producing HFC-125 comprising the steps of:
- (1-ii-a) reacting PCE and HF in the presence of catalyst at a reaction temperature in the range between 60.degree. C. and 150.degree. C. in a liquid phase first reaction step so as to obtain a first reaction mixture comprising HCFC-123 and/or HCFC-122,
- (1-ii-b) obtaining a first fraction from the first reaction mixture which fraction comprises HCFC-123 and/or HCFC-122 and HCl and a portion of unreacted HF,
- (1-ii-c) obtaining a fifth fraction by removing HCl from the first fraction which contains HCl,
- (1-ii-d) reacting the fifth fraction, optionally with additional HF, in the presence of catalyst at a reaction temperature in the range between 250.degree. C. and 450.degree. C. in a vapor phase second reaction step so as to obtain a second reaction mixture comprising HCFC-123, HCFC-124, HFC-125, HCl and HF,
- (1-ii-e) separating the second reaction mixture into three fractions: a second fraction which comprises most of HCFC-123 and/or HCFC-124 of the second reaction mixture and HF entrained therewith, a third fraction which comprises most of HFC-125 and HCl of the second reaction mixture, and a fourth fraction which comprises the rest of HF,
- (1-ii-f) recirculating the second fraction to the step (1-ii-d) and reacting it together there,
- (1-ii-g) recirculating the fourth fraction to the step (1-ii-a) and/or the step (1-ii-d) and reacting it together there, and
- (1-ii-h) separating out HFC-125 from the third fraction.
- 2. The process according to claim 1 wherein the steps (1-ii-b) and (1-ii-c) are carried out in a single step.
- 3. The process according to claim 1 wherein in the step (1-ii-g), recirculating is carried out after HF is added to the fourth fraction.
- 4. The process according to claim 1 wherein in the step (1-ii-f), recirculating is carried out after HF is added to the second fraction.
- 5. The process according to claim 1 wherein the first fraction is pressurized between the steps (1-ii-b) and (1-ii-c), and/or the second reaction mixture is pressurized between the steps (1-ii-d) and (1-ii-e).
- 6. The process according to any one of claims 1 to 5 wherein the catalyst for fluorination in the vapor phase second reaction step is fluorinated chromium oxide prepared by treating chromium oxide as a base material so as to have a specific surface area of at least 180 m.sup.2 /g.
Priority Claims (1)
Number |
Date |
Country |
Kind |
7-36793 |
Feb 1995 |
JPX |
|
Parent Case Info
This application is a 371 of PCT/JP96/00401 filed Feb. 22, 1996.
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
102e Date |
371c Date |
PCT/JP96/00401 |
2/22/1996 |
|
|
8/20/1997 |
8/20/1997 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO96/26172 |
8/29/1996 |
|
|
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
4258225 |
Feiring |
Mar 1981 |
|
4911792 |
Manzer et al. |
Mar 1990 |
|
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EPX |
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Jun 1990 |
JPX |
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Jun 1993 |
JPX |
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Oct 1992 |
WOX |
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