Method for selective removal of hydrogen sulfide from gas mixtures which also contain carbon dioxide

摘要

A process is disclosed for the selective removal of hydrogen sulphide from gaseous mixtures also containing carbon dioxide, which comprises essentially an absorption by means of a mixture of a low-boiling tertiary amine and of an organic solvent, with a water content not greater than 25% by weight, and a regeneration in a stripping column of the same absorbing solution and possibly an expansion stage between the absorption zone and the regeneration zone, and is characterized in that there are brought into contact with water in the upper absorption zone, or in a zone external to it, and in the upper stripping zone, or in a zone external to it, the gaseous effluents from the said zone. IMAGE