Method of removing carbon dioxide from gaseous mixtures

摘要

In a process for removing carbon dioxide from a gaseous mixture using an isothermal cycle of absorption with an aqueous solution containing an alkali and As2O3; and regeneration of the exhausted scrubbing liquor by stripping with stream, the absorption and regenerating steps are carried out an elevated temperature between 80 DEG and 100 DEG C. If desired, the major portion of the carbon dioxide may be removed in a first absorption regeneration cycle at below 100 DEG C. and a further amount of carbon dioxide may be removed in a second cycle which is effected at a temperature above 100 DEG C. The preferred absorbent is a solution of potassium carbonate, exemplified as 25% by weight K2CO3 solution containing 140 g/litre of As2O3.