Patent US3917799A successfully refreshed from Google Patents.
US3917799A
Expired / Lapsed
US
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Sulfur oxide adsorption and recovery
Assignee: Westvaco Corp
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Filing: 1973-02-26
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Granted: 1975-11-04
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Expires: 1993-02-26
Abstract
Abstract A process for removing sulfur oxides from gas streams whereby the sulfur oxides are adsorbed onto a carbonaceous adsorbent and recovering sulfur dioxide from the spent adsorbent by contacting the adsorbent with an oxide-reducing gas, i.e., hydrogen sulfide, whereby the adsorbed sulfur oxides having been adsorbed as sulfuric acid and sulfur trioxide are reduced.
Inventors
- 👤 Samuel L Torrence
- 👤 William C Walker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:09
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/02; B01D53/06; B01D53/10; B01D53/12; B01D53/04; B01D53/34; B01D53/46; B01D53/48; B01D53/50; B01D53/508; C; C01; C01B; C01B17/00; C01B17/02; C01B17/04; C01B17/0404; C01B17/0426; C01B17/0473; C01B17/48; C01B17/50; C01B17/60; B01D2253/00; B01D2253/10; B01D2253/102; B01D2257/00; B01D2257/30; B01D2257/302; B01D2257/304
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
85 words
A PROCESS FOR REGENERATINGA HARD GRANULAR ACTIVATED CARBON ADSORBENT HAVING SULFURIC ACID ADSORBENT THEREON COMPRISING, CONTAINING THE ACTIVATED CARBON HAVING SULFURIC ACID ADSORBENT THEREON WITH AN OXID-REDUCING GAS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN SULFIDE AND CARBONYL SULFIDE AT A TEMPERATURE BETWEEN AMBIENT AND ABOUT 570*F. AND SUFFICIENT TO REDUCE THE ADSORBED SULFURIC ACID TO AT LEAST ONE SUBSTANCE FROM THE GROUP CONSISTING OF ELEMENTAL SULFUR AND SULFUR DIOXIDE WITHOUT SUBSTANTIAL BURN-OFF OF ACTIVATED CARBON, AND REMOVING THE THUS-REDUCED SUBSTANCE FROM SAID ACTIVATED CARBON.
Claim 2
Dependent Claim
85 words
A PROCESS FOR REGENERATINGA HARD GRANULAR ACTIVATED CARBON ADSORBENT HAVING SULFURIC ACID ADSORBENT THEREON COMPRISING, CONTAINING THE ACTIVATED CARBON HAVING SULFURIC ACID ADSORBENT THEREON WITH AN OXID-REDUCING GAS SELECTED FROM THE GROUP CONSISTING OF HYDROGEN SULFIDE AND CARBONYL SULFIDE AT A TEMPERATURE BETWEEN AMBIENT AND ABOUT 570*F. AND SUFFICIENT TO REDUCE THE ADSORBED SULFURIC ACID TO AT LEAST ONE SUBSTANCE FROM THE GROUP CONSISTING OF ELEMENTAL SULFUR AND SULFUR DIOXIDE WITHOUT SUBSTANTIAL BURN-OFF OF ACTIVATED CARBON, AND REMOVING THE THUS-REDUCED SUBSTANCE FROM SAID ACTIVATED CARBON.
Claim 3
Dependent Claim
12 words
The process of claim 1 wherein said reduced substance is sulfur dioxide.
Claim 4
Dependent Claim
41 words
The process of claim 1 wherein said activated carbon having sulfuric acid adsorbed thereon is contacted with hydrogen sulfide at a temperature below 250*F. to convert all of said adsorbed sulfuric acid and hydrogen sulfide to elemental sulfur and water vapor.
Claim 5
Dependent Claim
12 words
The process of claim 1 wherein said oxide-reducing gas is hydrogen sulfide.
Claim 6
Dependent Claim
12 words
The process of claim 1 wherein said oxide-reducing gas is carbonyl sulfide.
Claim 7
Dependent Claim
18 words
The process of claim 1 wherein said activated carbon is treated at a temperature between 250* and 570*F.
Claim 8
Dependent Claim
126 words
A continuous process for removing sulfur oxides from an oxygen-containing gas stream comprising; a. passing the gas stream into contact with a hard granular activated carbon adsorbent at a temperature between 200*F. and 450*F. to adsorb the sulfur oxides onto said activated carbon adsorbent as sulfuric acid, b. continuously regeneraTing said activated carbon adsorbent having sulfuric acid adsorbed thereon by contacting said adsorbent with an oxide-reducing gas from the group consisting of hydrogen sulfide and carbonyl sulfide at a temperature between 250* and 570*F. for a period sufficient to reduce said adsorbed sulfuric acid to a member from the group consisting of sulfur dioxide, elemental sulfur and combinations thereof without substantial burn-off of activated carbon, and c. removing said reduced member from said activated carbon adsorbent.
Claim 9
Dependent Claim
126 words
A continuous process for removing sulfur oxides from an oxygen-containing gas stream comprising; a. passing the gas stream into contact with a hard granular activated carbon adsorbent at a temperature between 200*F. and 450*F. to adsorb the sulfur oxides onto said activated carbon adsorbent as sulfuric acid, b. continuously regeneraTing said activated carbon adsorbent having sulfuric acid adsorbed thereon by contacting said adsorbent with an oxide-reducing gas from the group consisting of hydrogen sulfide and carbonyl sulfide at a temperature between 250* and 570*F. for a period sufficient to reduce said adsorbed sulfuric acid to a member from the group consisting of sulfur dioxide, elemental sulfur and combinations thereof without substantial burn-off of activated carbon, and c. removing said reduced member from said activated carbon adsorbent.
Claim 10
Dependent Claim
18 words
The process of claim 7 wherein said gas stream is contacted at a temperature between 200*F. and 260*F.
Claim 11
Dependent Claim
16 words
The process of claim 7 wherein said continuous process is carried out in a fluidized bed.
Claim 12
Dependent Claim
12 words
The process of claim 7 wherein said oxide-reducing gas is hydrogen sulfide.
Claim 13
Dependent Claim
29 words
The process as defined in claim 7, further comprising; d. recycling the activated carbon adsorbent from which said reduced member has been removed into contact with said gas stream.
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) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |