Selective removal of (in)organic sulphur cpds. from gases - by scrubbing with diaza heterocyclic solvent with unsatd. and/or substd-alkyl substd. nitrogen, etc.

摘要

Selective removal of inorganic and/or organic S cpds. e.g. H2S, COS, CS2 and mercaptans from gases contg. H2, N2, Ar, CO2, CO and/or aliphatic hydrocarbons is effected by scrubbing with a physical solvent comprising a heterocyclic cpd. (I) with 5 or more ring members, including two N atoms that are double-bonded and/or single-bonded and substd. by an organic gp., provided that the ring is N- and/or C-substd. by at least one non-alkyl substit. selected from dialkylaminoalkyl, alkanoylalkyl, alkoxyalkyl, dialkylcarbamoylalkyl, dialkylpolyaminoalkyl and polyalkoxyalkyl. Pref. (I) is 1-methyl-3-dimethylaminoethyl-imidazolidine, 1-methyl-4-dimethylaminoethyl-2-piperazinone, 1-methyl-4-dimethylaminoethyl-piperazine or 1,3-dimethyl-5-dimethylam ino-hexahydropyrimidine. ADVANTAGE - Cpds. (I) have a greater H2S/CO2 selectivity than conventional solvents such as N-methylpyrrolidone and polyethylene glycol dialkyl ethers. (12pp Dwg.No.0/1)