Desulphurizing catalytic composition and its use in removing hydrogen sulphide and sulphur dioxide from a gas

• Main Authors: Dezael, Claude, Lecomte, Fabrice
• Format: Patent
• Language: English
• Published: 30.09.2003

The present invention concerns a composition, particularly for converting hydrogen sulphide and sulphur dioxide to sulphur, and its use in a process for the treatment of a gaseous effluent containing the composition. A desulphurizing composition for the treatment of CLAUS plant tail gases, comprises:an organic solvent A with a boiling point of more than 200° C. at atmospheric pressure;a catalyst composition B of at least one alkali- or alkaline-earth salt (S) of an organic monoacid or an organic polyacid which has at least one dissociation constant value (pK) in the range 2.2 to 8 such as formic acid, acetic acid, ascorbic acid, fumaric acid, maleic acid, malonic acid, oxalic acid, tartaric acid, benzoic acid, salicyclic acid, and sulphosalicyclic acid; at least one complexing agent (C) such as an alkali or alkaline-earth salt or a ferrous or ferric salt of a mono- or poly-aminocarboxylic acid, citric acid, a sulphocyanide ion, a ferrocyanide ion, a ferricyanide ion, a phosphate ion, a pyrophosphate ion, a fluoride ion and/or a thiosulphate ion; and water (W), in the following proportions by weight:S=0.1% to 30%;C=0.001% to 30%;W=balance.