PATENTS

      1533.  ------.  [I. G. FARBENINDUSTRIE, A. G.]  [Recovery of Higher Molecular-Weight Carboxylic Acids or Their Salts.]  German Patent Appl. I 67,224, OZ 12,205. filed June 19. 1940 (Cl. IV d-12 o).  FIAT Reel 163. frames 2,005-2,009: PB 25,607: Meyer Transl. PC-S-IV.  Wax Oxidation, vol. 3. chap. 32, 1949, p. 3.

            In recovering higher molecular weight carboxylic acids or their salts from mixtures containing unsaponifiable or unsaponified organic substances, such as the oxidation products of paraffins, middle oils, the hydrogenation products of CO, coal, and tar, the saponified mixture is extracted with fat solvents (gasoline or other liquid hydrocarbons) with the addition of such monovalent alcohols, ethers or esters thereof, or ketones with 3-6 C atoms in the molecule (propyl alcohol, acetone and methylethylketone), which are highly miscible with the fat solvents employed.  By means of this process crude fatty acids are obtained that have a content of only 0.1-0.3% unsaponifiable constituents.