Patent ID: 7459011

Claim:
Method for processing a natural gas containing at least one of the following acid compounds: hydrogen sulfide, carbon dioxide, mercaptans, and carbonyl sulfide, where the following steps are taken: a) the natural gas is brought into contact with a solvent that takes up the acid compounds so as to obtain a purified gas and a solvent charged with acid compounds, b) the solvent charged with acid compounds is regenerated so as to obtain a regenerated solvent and release a gaseous effluent containing acid compounds and a fraction of solvent, characterized in that the following steps are carried out: c) the gaseous effluent is brought into contact with a non-aqueous ionic liquid so as to obtain a gas phase containing acid compounds and an ionic liquid charged with solvent, the general formula of the ionic liquid being Q + A − , where Q + designates an ammonium, phosphonium, and/or sulfonium cation, and A − designates an anion able to form a liquid salt, wherein the Q + cation has one of the following general formulas: R 1 R 2 N + ═CR 3 —R 5 —R 3 C═N + R 1 R 2 and R 1 R 2 P + ═CR 3 —R 5 —R 3 C═P + R 1 R 2 where R 1 , R 2 , and R 3 represent hydrogen or a hydrocarbyl with 1 to 30 carbon atoms and where R 5 represents an alkylene or phenylene residue, and d) the ionic liquid charged with solvent is regenerated to separate the solvent and recover a solvent-impoverished ionic liquid.