US4940824A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for removing vinylidene chloride from 1,1-dichloro-1-fluoroethane
Assignee: Honeywell International Inc
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Filing: 1989-12-14
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Granted: 1990-07-10
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Expires: 2009-12-14
Abstract
Abstract Vinylidene chloride can be substantially removed from a stream of CFC-141b over a carbon molecular sieve having a mean pore size of about 4.2 to 4.5 Angstroms.
Inventors
- 👤 Stephen F. Yates
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:02
CPC Classifications
C; C07; C07C; C07C19/00; C07C19/08; C07C17/00; C07C17/38; C07C17/389
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
63 words
A process for purifying 1,1-dichloro-1-fluoroethane (CFC-141b) containing about 200 to 900 wt.ppm vinylidene chloride comprising passing said 1,1-dichloro-1-fluoroethane over a carbon molecular sieve having a mean pore size between about 4.2 to 4.5 Angstroms at a temperature of -20° C. to 60° C. and a pressure of about 100 to 500 kPa and recovering 1,1-dichloro-1-fluoroethane containing less than 200 wt.ppm of vinylidene chloride.
Claim 2
Dependent Claim
63 words
A process for purifying 1,1-dichloro-1-fluoroethane (CFC-141b) containing about 200 to 900 wt.ppm vinylidene chloride comprising passing said 1,1-dichloro-1-fluoroethane over a carbon molecular sieve having a mean pore size between about 4.2 to 4.5 Angstroms at a temperature of -20° C. to 60° C. and a pressure of about 100 to 500 kPa and recovering 1,1-dichloro-1-fluoroethane containing less than 200 wt.ppm of vinylidene chloride.
Claim 3
Dependent Claim
38 words
The process of claim 1 wherein said carbon molecular sieve is a fixed bed of particles, the 1,1-dichloro-1fluoroethane is a gas, and the gas hourly space velocity of said 1,1-dichloro-1-fluoroethane is about 130 to 1500 hr -1 .
Claim 4
Dependent Claim
38 words
The process of claim 1 wherein said carbon molecular sieve is a fixed bed of particles, the 1,1-dichloro-1fluoroethane is a liquid, and the liquid hourly space velocity of said 1,1-dichloro-1-fluoroethane is about 1 to 15 hr -1 .
Claim 5
Dependent Claim
18 words
The process of claim 1 wherein the recovered 1,1-dichloro-1-fluoroethane contains less than 50 wt. ppm of vinylidene chloride.
References Cited (Backward Citations)
US2894044A
Cited
GB846677A
Cited
US3833676A
Cited
JPS6440436A
Cited
US4820681A
Cited
US4849558A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-07-09 | 1994-01-08 | 1994-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-09 | 1998-01-08 | 1998-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-09 | 2002-01-08 | 2002-07-10 | $7700.00 | Window Closed / Lapsed |