PATENTS

      1536.  ------.  [I. G. FARBENINDUSTRIE, A. G.]  [Recovery of Low-Molecular-Weight Organic Oxygenated Products in the Oxidation of Nonaromatic Hydrocarbons.]  German Patent Appl. I 68,657, OZ 12,543, filed Jan. 15. 1941 (Cl. IV d-12 o).  FIAT Reel 164. frames 3,244-3,248; PB 25,608; Meyer Transl. PC-S-IV, Wax Oxidation, vol. 3, chap. 51, 1949, p. 39.

            In the oxidation of higher molecular-weight nonaromatic hydrocarbons with O₂ or gases containing it, there are formed, besides higher molecular weight carboxylic acids, hydroxy acids, esters, aldehydes and ketones, considerable amounts of low-molecular-weight oxygenated compounds, chiefly lower fatty acids, which contain up to about 10 C atoms in the molecule, besides hydroxy acids and lactones of the same molecular size.  They are obtained in the form of an aqueous condensate containing up to 40% of these compounds.  It has been found that these low molecular weight oxidation products can be recovered in pure and H₂O-free condition if the aqueous portion is extracted with a solvent mixture consisting of methyl-ethyl ketone and an either or hydrocarbon b.<100º and, with H₂O, forms an azeotrope with a minimum boiling point.  A mixture of methyl-ethyl ketone and benzene in proportions of 70:30 is a satisfactory mixture.