PATENTS

      1463.  ------.  [I. G. FARBENINDUSTRIE, A. G.]  [Process for the Preparation of Olefins From Gaseous or Vaporized Saturated Hydrocarbons.]  German Patent Appl. I 52,516, OZ 8,906, filed June 7, 1935 (Cl. IV d-12 o). Meyer Transl. PC-S-II, Fischer-Tropsch. Vol 1, chap. 70, 1948, p. 178.

            In preparing olefins from gaseous or vaporized saturated hydrocarbons (except CH₄) by addition of O₂ to the separately preheated hydrocarbons, the O₂ on contacting the hydrocarbons is so greatly diluted by introducing at least 1 of the gases with high rate of flow, or by mixing the gases under reduced pressure, that the formation of flame or local overheating does not occur.  Example: Vapors of 3.1 kg. per hr. of middle oil from the hydrogenation of CO are introduced into the central line of a mixer of the type of a H₂O-jet pump, while through the jacket of the mixer, 530 l. of O₂ are passed per hr.  The oil vapor is preheated to 600º-650º and the O₂ to 500º.  After passing through the apparatus heated to 820º, the reaction product is cooled, the liquid constituents separated, and the gases drawn off by a vacuum pump.  3 m.³ of gas are obtained hourly containing 33% by volume of C₂H₄ and 20% higher olefins consisting almost entirely of propylene and butylenes.  Based on the oil charged and 1 pass, about 75% by weight of olefins is obtained.