US3907972A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Absorbing SO{HD 2 {B with polyacrylic acid solution
Assignee: Celanese Corp
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Filing: 1973-04-30
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Granted: 1975-09-23
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Expires: 1993-04-30
Abstract
Abstract In the recovery of sulfur dioxide (SO2) from an SO2-containing gas by contacting said gas with an aqueous absorbing solution, thereafter treating said solution to remove the SO2 therefrom at least in part, and re-cycling the SO2-freed absorbing solution, the improvement which comprises employing as said absorbing solution an aqueous solution of a polyalkenoic acid such as polyacrylic acid or polymethacrylic acid of a molecular weight of at least about 200. Preferably the molecular weight of the polyalkenoic acid is below about 6000 and the pH of the solution is about 3.2 to 4. The SO2 is removed from the absorbing solution almost quantitatively with H2S, sulfur being produced in the reaction.
Inventors
- 👤 Adin Lee Stautzenberger
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:29
CPC Classifications
C; C01; C01B; C01B17/00; C01B17/02; C01B17/04; C01B17/05; B; B01; B01D; B01D53/00; B01D53/14; B01D53/1493; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/507; C01B17/48; C01B17/50; C01B17/60
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
84 words
IN THE RECOVERY OF SULFUR DIOXIDE (SO2) FROM AN SO2-CONTAINING GAS WITH AN AQUEOUS ABSORBING SOLUTION, THEREAFTER TREATING SAID SOLUTION TO REMOVE THE SO2 THEREFROM AT LEAST IN PART FOLLOWED BY RE-CYCLING THE SO2-FREED ABSORBING SOLUTION, THE IMPROVEMENT WHICH COMPRISES EMPLOYING AS SAID ABSORBING SOLUTION AN AQUEOUS SOLUTION OF A POLYACID OF A MOLECULAR WEIGHT OF AT LEAST ABOUT 200 AND COMPRISING PREDOMINANTLY AT LEAST ONE MEMBER OF THE GROUP CONSISTING OF POLYACRYLIC ACID, POLYMETHACRYLIC ACID, AND COPOLYMERS OF ACRYLIC ACID AND METHACRYLIC ACID.
Claim 2
Dependent Claim
84 words
IN THE RECOVERY OF SULFUR DIOXIDE (SO2) FROM AN SO2-CONTAINING GAS WITH AN AQUEOUS ABSORBING SOLUTION, THEREAFTER TREATING SAID SOLUTION TO REMOVE THE SO2 THEREFROM AT LEAST IN PART FOLLOWED BY RE-CYCLING THE SO2-FREED ABSORBING SOLUTION, THE IMPROVEMENT WHICH COMPRISES EMPLOYING AS SAID ABSORBING SOLUTION AN AQUEOUS SOLUTION OF A POLYACID OF A MOLECULAR WEIGHT OF AT LEAST ABOUT 200 AND COMPRISING PREDOMINANTLY AT LEAST ONE MEMBER OF THE GROUP CONSISTING OF POLYACRYLIC ACID, POLYMETHACRYLIC ACID, AND COPOLYMERS OF ACRYLIC ACID AND METHACRYLIC ACID.
Claim 3
Dependent Claim
21 words
The process of claim 1, wherein the polyacid comprises predominantly polyacrylic acid having a molecular weight not greater than about 200,000.
Claim 4
Dependent Claim
43 words
The process of claim 2, wherein the polyacrylic acid concentration in said aqueous solution is about 5 to 50 percent by weight based on the polyacrylic acid and water and wherein the polyacrylic acid has a molecular weight of about 200 to 6000.
Claim 5
Dependent Claim
24 words
The process of claim 1, wherein the pH of the polyacid solution is adjusted to about 3.2 to 4 prior to said absorption step.
Claim 6
Dependent Claim
28 words
The process of claim 1, wherein the treatment to remove SO2 from the absorbing solution comprises contacting said solution with H2S thereby to convert the SO2 to sulfur.
Claim 7
Dependent Claim
58 words
The process of claim 5, wherein the polyacid is polyacrylic acid having a molecular weight not greater than about 6000, its concentration in the absorbing solution is about 10 to 30 percent by weight based on polyacrylic acid and water, and the pH of the solution is adjusted to about 3.2 to 4 prior to said absorption step.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |