US3589104A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of chemicals from off-gases
Assignee: Dow Chemical Co
•
Filing: 1969-06-26
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Granted: 1971-06-29
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Expires: 1989-06-26
Abstract
Abstract An improved method for the recovery of valuable organic compounds and deleterious air polluting chemicals from watercontaining process off-gases which comprises (1) contacting the process off-gases with a cold surface upon which a film of watermiscible liquid is maintained; (2) separating the noncondensible gases from the condensate which forms upon contact of the offgases with the cold wall and the water-miscible liquid; (3) separating the water-miscible liquid, water and condensate one from the other; (4) returning the water-miscible liquid to the first step to form the film on the cold wall and (5) recovering the condensates free of the water-miscible liquid and water.
Inventors
- 👤 John E Panzarella
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:26
CPC Classifications
B; B01; B01D; B01D51/00; B01D51/10; B01D5/00; B01D5/0003; B01D5/0012; B01D5/0078; B01D5/009; B01D5/0093; B01D5/0096; B01D53/00; B01D53/34; B01D53/46; B01D53/68; B01D53/70; B01D8/00
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
21 words
The process of claim 1 wherein the miscible organic liquid is concentrated and returned to step A to form the film.
Claim 2
Dependent Claim
16 words
The process of claim 1 wherein the water-miscible liquid is also immiscible with the condensable gases.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein the recovered organic compounds are C1 to C4 chlorinated hydrocarbons.
Claim 4
Dependent Claim
16 words
The process of claim 4 wherein said chlorinated hydrocarbons are recovered from an oxychlorination reactor off-gas.
Claim 5
Dependent Claim
16 words
The method of claim 1 wherein the miscible organic liquid is a C2 or C3 glycol.
Claim 6
Dependent Claim
11 words
The method of claim 6 wherein the glycol is ethylene glycol.
Claim 7
Dependent Claim
30 words
The method of claim 1 wherein the miscible organic liquid is a mixture of 40 to 80 weight percent of ethylene glycol and 60 to 20 weight percent of H2O.
Claim 8
Dependent Claim
33 words
The process of claim 4 wherein the miscible organic Liquid is ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, methanol, ethanol, propanol, methoxy ethanol, ethoxy ethanol or propoxy ethanol.
Claim 9
Dependent Claim
17 words
The process of claim 9 wherein the hot gases are cooled to between 0* and -60* C.
References Cited (Backward Citations)
US24433A
Cited
US3347019A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-06-28 | 1974-12-28 | 1975-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |