2594.     PAVCEK, P. L.  Production of Fatty Acids From Byproducts of the Fischer-Tropsch Process.  CIOS Rept. XXVIII-35, 1945, 3 pp., PB 4,291; TOM Reel 198.]

        Paraffins produced by the Fischer-Tropsch process (m. p. 50°-55° and consisting of C₂₀-C₂₆ hydrocarbons) are oxidized with air at 130°-150°, using KMnO₄ as catalyst in Al towers.  Oxidation is not complete and the Mn salts of the fatty acids must be separated from the unreacted paraffin by means of alcohol and C₆H₆.  After neutralization with NaOH or Na₂CO₃, the crude soaps are steam-distilled at 250°.  The lower fatty acids, such as formic, acetic, propionic, and butyric, come off immediately and the hydroxy acids are converted to unsaturated acids.  Keto acids also are removed at this point by the Hader process.  The olefinic and saturated acids remaining as the Na salts from the above distillation are set free with HNO₃, and the Na-No₃ is removed.  The free acids are steam distilled by the Wecker method of forcing water into the hot fat.  This method avoids polymerization and keto acid formation and high-grade fatty acids are obtained.  The fatty acids are esterified with glycerol (made from propylene) to form soaps or edible triglycerides.  Oppau and Witten utilize 20,000 tons/yr. of paraffin, the Märkische Seifenindustrie uses even larger quantities.  The overall yield of fatty acids is about 50%.  The C₆-H₁₀ alcohols obtained as byproducts form excellent plasticizers when esterified with phthalic anhydride (abs. 186).