PATENTS

      1479.  ------.  [I. G. FARBENINDUSTRIE, A. G.]  [Producing Unsaturated Hydrocarbons.]  French Patent 843,844, July 11, 1939.  Chem. Abs. vol. 34, 1940. p. 7091.

            Mixture of hydrocarbons rich in unsaturated constituents is obtained from a mixture of CO and H₂ by using for the catalytic reaction a gas containing less than 2 parts by volume of H₂ for every part by volume of CO and adding new quantities of H₂ in the course of the reaction.  As catalysts are used Co or Ni on appropriate supports, mixtures of Fe and Cu, the Fe obtained by reduction of ferrous-ferric oxide in presence of silicic acid.  Ti oxide or alumina, and metals of the Fe group with Mn and Cu or with Al or with Th oxide.  Thus, a gas containing 0.9-1.5 parts H₂ for every part CO is caused to pass, under atmospheric pressure and at a temperature ranging 160º-350º, over 1 of the above mentioned catalysts; the ratio of H₂:CO is maintained during the reaction by adding new quantities of H₂.  The contents in olefins of the more volatile fractions of the final products amount to 50-80%.