Patent ID: 8231713

Claim:
A process for selective removal of COS from a gas stream containing COS and CO 2 with minimal absorption of CO 2 from the stream, said process comprising contacting the gas stream with a solvent composition comprising a) at least one polyalkylene glycol alkyl ether of the formula R 1 O-(Alk-O) n ,—R 2 (I) wherein R 1 , is an alkyl group having from 1 to 6 carbon atoms; R 2 is hydrogen or an alkyl group having from 1 to 4 carbon atoms; Alk is an alkylene group, branched or unbranched, having from 2 to 4 carbon atoms; and n is from 1 to 10; and b) at least one alkanolamine compound of the formula R 3 NHR 4 OR 6 (II) Or at least one piperazine compound of formula wherein R 3 is hydrogen, an alkyl group having from 1 to 6 carbon atoms, or the R 4 OH group; R 4 is a branched or unbranched alkylene group having from 1 to 6 carbon atoms; R 5 , independently in each occurrence, is hydrogen or an hydroxyalkyl group having from 1 to 4 carbon atoms; and R 6 is hydrogen, an alkyl group having from 1 to 6 carbon atoms or an hydroxyalkyl group having from 1 to 4 carbon atoms; wherein additional CO 2 absorption due to the presence of component b) is less than ⅓ of the CO 2 present in the gas stream.