Abstract: For the selective removal of sulfur from gases, a physical scrubbing agent is used, comprising a heterocycle having five or more ring atoms, which contains two heteroatoms, one of which is nitrogen and the other of which is oxygen or nitrogen; and the heteroatoms in the rings of even member number of atoms occupy; one of the positions from 1,2 to 1,n/2 and, in the rings of uneven member number of atoms occupy one of the positions from 1,2 up to 1, (n-1)/2. Further, the nitrogen heteroatom(s) present in the ring is/are either double bonded or single bonded but, if single bonded, the nitrogen is organo-substituted.

Abstract: For scrubbing C.sub.2+ or C.sub.3+ hydrocarbons from gaseous mixture containing hydrocarbons and/or inerts like H.sub.2 N.sub.2, CO and possibly acid gases, e.g. CO.sub.2 H.sub.2 S, COS e.g. natural gas and the like, the scrubbing medium consists essentially of compounds having one to two rings formed by 5 or 6 carbon atoms, wherein the compounds comprise, in total, at least 9 and at most 17 carbon atoms, and the rings are saturated unsaturated or partially saturated especially alkylated ring compounds of 9 or 10 carbon atoms, e.g. isomeric forms of trimethylbenzene, propylbenzene, propylcyclohexane, tetrahydronaphthalene, decahydronaphthalene.

Abstract: For scrubbing C.sub.2+ or C.sub.3+ hydrocarbons from gaseous mixture containing hydrocarbons and/or inerts like H.sub.2' N.sub.2, CO and possibly acid gases, e.g. CO.sub.2 H.sub.2 S, COS e.g., natural gas and the like, the scrubbing medium consists essentially of compounds having one to two rings formed by 5 or 6 carbon atoms, wherein the compounds comprise, in total, at least 9 and at most 17 carbon atoms, and the rings are saturated unsaturated or partially saturated especially alkylated ring compounds of 9 or 10 carbon atoms, e.g. isomeric forms of trimethylbenzene, propylbenzene, propylcyclohexane, tetrahydronaphthalene, decahydronaphthalene.