Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
168 words
In the process for treating a hydrogen sulfide containing hydrogenated Claus process tail gas to convert the hydrogen sulfide to elemental sulfur in which said Claus process tail gas is contacted with an aqueous alkaline washing solution containing a water-soluble metal vanadate and a water-soluble anthraquinone disulfonate to yield an effluent gas of reduced sulfur content, thereafter the solution is contacted with an oxygen-containing gas to form elemental sulfur and to regenerate said solution, said elemental sulfur is recovered from said solution and said regenerated solution is recycled to said gas contacting step, said contact between said Claus process tail gas and said solution resulting in the chemical consumption of said anthraquinone disulfonate, the improvement comprising: maintaining in said solution an effective amount of a solubilized material selected from the group consisting of water-soluble phenols, the water-soluble salts and hydrates of phenols, and mixtures thereof, said solubilized material having a deactivating value of at least about 15 whereby the chemical consumption of said anthraquinone disulfonate is substantially reduced.
Claim 2
Dependent Claim
168 words
In the process for treating a hydrogen sulfide containing hydrogenated Claus process tail gas to convert the hydrogen sulfide to elemental sulfur in which said Claus process tail gas is contacted with an aqueous alkaline washing solution containing a water-soluble metal vanadate and a water-soluble anthraquinone disulfonate to yield an effluent gas of reduced sulfur content, thereafter the solution is contacted with an oxygen-containing gas to form elemental sulfur and to regenerate said solution, said elemental sulfur is recovered from said solution and said regenerated solution is recycled to said gas contacting step, said contact between said Claus process tail gas and said solution resulting in the chemical consumption of said anthraquinone disulfonate, the improvement comprising: maintaining in said solution an effective amount of a solubilized material selected from the group consisting of water-soluble phenols, the water-soluble salts and hydrates of phenols, and mixtures thereof, said solubilized material having a deactivating value of at least about 15 whereby the chemical consumption of said anthraquinone disulfonate is substantially reduced.
Claim 3
Dependent Claim
25 words
The process defined in claim 1 wherein the concentration of said solubilized material in said solution is between about 0.01 and 10 grams per liter.
Claim 4
Dependent Claim
19 words
The process defined in claim 1 wherein said solubilized material is phenol and the soluble salts and hydrates thereof.
Claim 5
Dependent Claim
35 words
The process defined in claim 1 wherein the solubilized material is o-cresol, the soluble salts and hydrates thereof, p-cresol, the soluble salts and hydrates thereof, m-cresol, the soluble salts and hydrates thereof, and mixtures thereof.
Claim 6
Dependent Claim
20 words
The process as defined in claim 1 wherein said solubilized material comprises the soluble salts and hydrates of salicylic acid.
Claim 7
Dependent Claim
21 words
The process of claim 1 wherein said solubilized material in said solution has a deactivating value of at least about 16.
Claim 8
Dependent Claim
25 words
The process as defined in claim 1 wherein said solubilized material in said washing solution has a deactivating value of not less than about 18.
Claim 9
Dependent Claim
161 words
In the process for treating a hydrogen-sulfide-containing hydrogenated Claus process tail gas to convert the hydrogen sulfide to elemental sulfur in which said gas is contacted with an aqueous alkaline washing solution containing a water-soluble metal vanadate and a water-soluble anthraquinone disulfonate to yield an effluent gas of reduced hydrogen sulfide content, the solution thereafter is regenerated by contact with an oxygen-containing gas, elemental sulfur is recovered from said solution and said regenerated solution is recycled to said gas-contacting step and in which said anthraquinone disulfonate is being chemically consumed, the improvement which comprises: maintaining in solution about 0.1 to 2 gm/l of an organic complexing agent in said washing solution, said complexing agent being selected from the group consisting of phenol, o-cresol, m-cresol, p-cresol, the alkali metal salts and hydrates of salicylic acid, and mixtures thereof, said organic complexing agent having a deactivating value of at least about 16 whereby the chemical consumption of said anthraquinone disulfonate is substantially reduced.
Claim 10
Dependent Claim
161 words
In the process for treating a hydrogen-sulfide-containing hydrogenated Claus process tail gas to convert the hydrogen sulfide to elemental sulfur in which said gas is contacted with an aqueous alkaline washing solution containing a water-soluble metal vanadate and a water-soluble anthraquinone disulfonate to yield an effluent gas of reduced hydrogen sulfide content, the solution thereafter is regenerated by contact with an oxygen-containing gas, elemental sulfur is recovered from said solution and said regenerated solution is recycled to said gas-contacting step and in which said anthraquinone disulfonate is being chemically consumed, the improvement which comprises: maintaining in solution about 0.1 to 2 gm/l of an organic complexing agent in said washing solution, said complexing agent being selected from the group consisting of phenol, o-cresol, m-cresol, p-cresol, the alkali metal salts and hydrates of salicylic acid, and mixtures thereof, said organic complexing agent having a deactivating value of at least about 16 whereby the chemical consumption of said anthraquinone disulfonate is substantially reduced.
Claim 11
Dependent Claim
27 words
The process as defined in claim 8 wherein said organic complexing agent is phenol, o-cresol, m-cresol, p-cresol, the alkali metal salts and hydrates thereof and mixtures thereof.