US5087778A
Expired / Lapsed
US
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Regeneration of zeolites used for purifying 1,1,1,2-tetrafluoroethane
Assignee: Honeywell International Inc
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Filing: 1990-04-10
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Granted: 1992-02-11
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Expires: 2010-04-10
Abstract
Abstract 1,1,1,2-Tetrafluoroethane (R134a) is purified to remove 50-10,000 wt. ppm of 2-chloro-1,1-difluoroethylene (R1122) by contacting with a zeolite or carbon molecular sieve having an average pore diameter of 3.8 to 4.8 Angstroms. The zeolite or carbon molecular sieve is regenerated by inert gas stripping residual R134a, followed by a regeneration at elevated temperatures using an inert gas. Regeneration of the zeolite or carbon molecular sieve is accomplished without the substantial reduction in capacity for impurities.
Inventors
- 👤 Stephen F. Yates
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:06
CPC Classifications
C; C07; C07C; C07C17/00; C07C17/38; C07C17/389; B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/16; B01J20/165; B01J20/18; B01J20/20; B01J20/30; B01J20/34; B01J20/3408; B01J20/3416; B01J20/3483; B01J20/3491
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
96 words
A method for regenerating zeolites or carbon molecular sieves used for removing 2-chloro-1,1-difluoroethylene (R1122) from 1,1,1,2-tetrafluoroethane (R134a) comprising: (a) removing R134a by stripping the zeolite or carbon molecular sieve with an inert gas at a temperature of about 0° to 60° C. and a pressure not higher than about 300 kPa; (b) separating and recovering R134a from the inert gas (c) removing R1122 from said zeolite by passing an inert gas over said zeolite or carbon molecular sieve at a temperature of about 150° to 300° C. and a pressure no higher than about 300 kPa.
Claim 2
Independent Claim
96 words
A method for regenerating zeolites or carbon molecular sieves used for removing 2-chloro-1,1-difluoroethylene (R1122) from 1,1,1,2-tetrafluoroethane (R134a) comprising: (a) removing R134a by stripping the zeolite or carbon molecular sieve with an inert gas at a temperature of about 0° to 60° C. and a pressure not higher than about 300 kPa; (b) separating and recovering R134a from the inert gas (c) removing R1122 from said zeolite by passing an inert gas over said zeolite or carbon molecular sieve at a temperature of about 150° to 300° C. and a pressure no higher than about 300 kPa.
Claim 3
Dependent Claim
30 words
The process of claim 1 wherein said inert gas of (a) is at least one member of the group consisting of nitrogen, argon, helium, carbon dioxide and low boiling fluorocarbons.
Claim 4
Dependent Claim
13 words
The process of claim 2 wherein said inert gas of (a) is nitrogen.
Claim 5
Dependent Claim
13 words
The process of claim 1 wherein said inert gas of (a) is air.
Claim 6
Dependent Claim
13 words
The process of claim 2 wherein said inert gas of (a) is R113.
Claim 7
Dependent Claim
30 words
The process of claim 1 wherein said inert gas of (c) is at least one member of the group consisting of nitrogen, argon, helium, carbon dioxide and low boiling fluorocarbons.
Claim 8
Dependent Claim
13 words
The process of claim 6 wherein said inert gas of (c) is nitrogen.
Claim 9
Dependent Claim
13 words
The process of claim 1 wherein said inert gas of (c) is air.
Claim 10
Dependent Claim
13 words
The process of claim 4 wherein said inert gas of (c) is R113.
Claim 11
Dependent Claim
15 words
The process of claim 1 wherein the pressure is no higher than about 100 kPa.
Claim 12
Dependent Claim
11 words
The process of claim 1 wherein said zeolite is calcium chabazite.
Claim 13
Dependent Claim
129 words
A process for purification of 1,1,1,2-tetrafluoroethane (R134a) by removing 2-chloro-1,1-difluoroethylene (R1122) by contacting said R134a with a zeolite or carbon molecular sieve wherein the improvement comprises regenerating said zeolite by a sequence of steps comprising: (a) removing R134a by stripping the zeolite or carbon molecular sieve with an inert gas at a temperature of 0° to 60° C. and a pressure of no higher than about 300 kPa; (b) separating from the inert gas of (a) the R-134a and returning the separated R134a to the purification process; (c) removing R1122 from said zeolite by passing an inert gas over said zeolite or carbon molecular sieve at a temperature of about 150° to 300° C. and a pressure of less than about 300 kPa; and, (d) disposing of the R1122.
Claim 14
Dependent Claim
129 words
A process for purification of 1,1,1,2-tetrafluoroethane (R134a) by removing 2-chloro-1,1-difluoroethylene (R1122) by contacting said R134a with a zeolite or carbon molecular sieve wherein the improvement comprises regenerating said zeolite by a sequence of steps comprising: (a) removing R134a by stripping the zeolite or carbon molecular sieve with an inert gas at a temperature of 0° to 60° C. and a pressure of no higher than about 300 kPa; (b) separating from the inert gas of (a) the R-134a and returning the separated R134a to the purification process; (c) removing R1122 from said zeolite by passing an inert gas over said zeolite or carbon molecular sieve at a temperature of about 150° to 300° C. and a pressure of less than about 300 kPa; and, (d) disposing of the R1122.
Claim 15
Dependent Claim
30 words
The process of claim 12 wherein said inert gas of (a) is at least one member of the group consisting of nitrogen, argon, helium, carbon dioxide and low boiling fluorocarbons.
Claim 16
Dependent Claim
13 words
The process of claim 13 wherein said inert gas of (a) is nitrogen.
Claim 17
Dependent Claim
11 words
The process of claim 12 wherein said inert gas is air.
Claim 18
Dependent Claim
11 words
The process of claim 13 wherein said inert gas is R113.
Claim 19
Dependent Claim
30 words
The process of claim 12 wherein said inert gas of (c) is at least one member of the group consisting of nitrogen, argon, helium, carbon dioxide and low boiling fluorocarbons.
Claim 20
Dependent Claim
13 words
The process of claim 17 wherein said inert gas of (c) is nitrogen.
Claim 21
Dependent Claim
11 words
The process of claim 12 wherein said zeolite is calcium chabazite.
Claim 22
Dependent Claim
15 words
The process of claim 12 wherein the pressure is no higher than about 100 kPa.
References Cited (Backward Citations)
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