US4098886A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas purification liquors
Assignee: British Gas PLC
•
Filing: 1977-02-16
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Granted: 1978-07-04
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Expires: 1997-02-16
Abstract
Abstract Thiosulphate ions present in gas purification liquors, particularly those employed for removing H 2 S by washing with aqueous alkaline solutions of vanadium compounds and anthraquinone disulphonic acids, are decomposed to sulphide and hydroxyl ions by exposing the liquor to a hydrogen rich gas at elevated temperature e.g., 650° C. The liquor may be evaporated and the solid residue subjected to decomposition. Any thiocyanate ions are hydrolyzed; it being necessary to mix steam with the hydrogen rich gas if a solid residue is being decomposed.
Inventors
- 👤 Thomas Nicklin
- 👤 Frederick Farrington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:44
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/02; C02F1/04; C02F1/048; B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/48; B01D53/52; B01D53/523; C01; C01B; C01B17/00; C01B17/02; C01B17/04; C01B17/05; C01B17/22; C01B17/24; C01B17/28; C01P; C01P2006/00; C01P2006/80; C02F1/24; C02F2103/00; C02F2103/18
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
88 words
A process for the decomposition of thiosulphate ions present in aqueous gas purification liquors employed for removing hydrogen sulphide from fuel gases or liquid hydrocarbons by means of a wash liquor containing vanadium compounds and sodium anthraquinone disulphonate, concentrating and cooling said liquors so as to crystallize out the sodium anthraquinone disulphonate, recovering the sodium anthraquinone disulphonate and exposing the resulting liquor or a solid residue derived therefrom by evaporation to a hydrogen-rich gas at a temperature of 300° to 800° C. in the absence of a catalyst.
Claim 2
Dependent Claim
88 words
A process for the decomposition of thiosulphate ions present in aqueous gas purification liquors employed for removing hydrogen sulphide from fuel gases or liquid hydrocarbons by means of a wash liquor containing vanadium compounds and sodium anthraquinone disulphonate, concentrating and cooling said liquors so as to crystallize out the sodium anthraquinone disulphonate, recovering the sodium anthraquinone disulphonate and exposing the resulting liquor or a solid residue derived therefrom by evaporation to a hydrogen-rich gas at a temperature of 300° to 800° C. in the absence of a catalyst.
Claim 3
Dependent Claim
36 words
A process as claimed in claim 1 in which thiocyanate ions are also present in the liquor, and a solid residue derived from said liquor is exposed to a mixture of hydrogen rich gas and steam.
Claim 4
Dependent Claim
23 words
A process as claimed in claim 1 in which the decomposition is carried out at a temperature of from 500° to 800° C.
Claim 5
Dependent Claim
45 words
A process as claimed in claim 1 in which said aqueous liquor is sprayed into a reducing flame at a temperature of from 500°- 700° C., said reducing flame conditions being achieved by burning in hydrocarbon fuel with less than the stoichiometric requirement of air.
Claim 6
Dependent Claim
28 words
A process as claimed in claim 3 in which additional hydrogen rich gas is admitted with the combustion product obtained by the incomplete combustion of a hydrocarbon fuel.
Claim 7
Dependent Claim
39 words
A process as claimed in claim 1 in which a solid residue derived by the evaporation of said liquor is contacted with a hydrogen rich gas in a rotary kiln, at a temperature of from 300° to 800° C.
Claim 8
Dependent Claim
20 words
A process as claimed in claim 6 in which the decomposition is carried out at a temperature of 650° C.
Claim 9
Dependent Claim
42 words
A process as claimed in claim 1 in which a solid residue derived by the evaporation of said liquor is contacted with a mixture of hydrogen rich gas and steam in a rotary kiln at a temperature of from 500°- 700° C.
Claim 10
Dependent Claim
16 words
A process as claimed in claim 1 in which said hydrogen rich gas is Town's Gas.
Claim 11
Dependent Claim
45 words
A process as claimed in claim 1 in which a solid residue derived from the evaporation of said liquor, is contacted with product of the incomplete combustion of a hydrocarbon fuel with air, at a temperature of at least 800° C. in a rotary kiln.
Claim 12
Dependent Claim
16 words
A process as claimed in claim 10 in which superheated steam is admitted to the kiln.
Claim 13
Dependent Claim
18 words
A process as claimed in claim 10 in which the hydrocarbon fuel is tar or heavy fuel oil.
Claim 14
Dependent Claim
29 words
A process as claimed in claim 1 in which the solid residue obtained after decomposition is leached with water and the water-soluble fraction is returned to the wash liquor.
Claim 15
Dependent Claim
48 words
A process as claimed in claim 1 in which an aqueous liquor containing both thiosulphate and thiocyanate ions is decomposed by injection into a reaction chamber maintained at a temperature of at least 600° C., said hydrogen rich gas being produced in situ by hydrolysis of the thiocyanate.
Claim 16
Dependent Claim
56 words
A process as claimed in claim 1 in which a solid residue derived by evaporation of a liquor containing both thiosulphate and thiocyanate ions is decomposed by contact, in a rotary kiln maintained at a temperature of at least 800° C. with superheated steam, said hydrogen-rich gas being produced in situ by hydrolysis of the thiocyanate.
Claim 17
Dependent Claim
111 words
In a process for the absorption and subsequent removal as sulphur of hydrogen sulphide from gases, gas mixtures and liquid hydrocarbons, in which the material-containing hydrogen sulphide is washed with an aqueous alkaline solution containing one or more anthraquinone disulphonic acids, in compound of a metal having at least two valency states, and if necessary a chelating or sequestering agent for retaining such metal compounds in solution, removing sulphur from the aqueous wash solution by froth flotation the improvement consisting in subjecting the thus formed sulphur containing froth and/or at least part of the liquor from which the sulphur has been removed to a decomposition process as claimed in claim 1.
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) | 1981-07-03 | 1982-01-02 | 1982-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-03 | 1986-01-02 | 1986-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-03 | 1990-01-02 | 1990-07-04 | $7700.00 | Window Closed / Lapsed |