PATENTS

      117.     BÄHR, H., AND BRAUS, K.  (I. G. Farbenindustire A. G.).  Hydrogen Sulfide Recovery From Gas Mixtures.  United States Patent 2,083,213, June 8, 1937, Chem. Abs., vol. 31, 1937, p. 5522.

Gas, such as waste gas from coal hydrogenation, containing both H₂S and CO₂ is scrubbed in the cold with a solution having an alkaline reaction and capable of taking up both H₂S and CO₂ and of giving them off on heating, such as a solution of alanine Na salt, while the solution is used in sprayed form and a gas-contact period of <5 sec. Is provided to effect recovery of a high proportion of H₂S on heating.