PATENTS

      1566.  ------.  [I. G. FARBENINDUSTRIE, A. G.]  Soaps:  Fatty Acids.  British Patent 482,277, Mar. 21, 1938.  Chem. Abs., vol. 32, 1938, p. 7297.

            Soaps, or fatty acids therefrom, freed from unpleasant odor, are obtained from nonaromatic hydrocarbons oxidized by air or other gas containing O₂ by treating the saponified oxidation products with steam at a temperature < that at which the unsaponifiables may be removed before or after, for example, by solvents, or by treatment with steam at the higher temperatures necessary but for a time to short to remove much of the malodorous substances.  Before saponification the oxidized products may be freed from readily soluble oxidation products of low boiling point by H₂O, acids, or organic solvents.  The odor-free soaps may be bleached by H₂O₂ or NaClO.  In an example, a mixture of crude scale wax with unsaponifiables from a previous oxidation is oxidized at 115º with air presence of KMnO₄, saponified at 230º under pressure with a 15% NaOH solution, diluted to a 20% soap solution with H₂O and EtOH, and extracted with benzine to remove unsaponifiables, the soap solution being then forced by a pump through a preheater under pressure and sprayed at 250º-300º into the tower: the H₂O, solvents and malodorous substances evaporated pass to a condenser, and the soap solution, no at about 150º, flows over Raschig rings against a current of steam from a pipe and is withdrawn through anther pipe.