GB534151A - Improved method for converting hydrocarbons - Google Patents

Abstract

534,151. Hydrocarbons. STANDARD OIL DEVELOPMENT CO. Aug. 22, 1939, No. 24167. Convention date, Jan. 7. Drawings to Specification. [Class 2 (iii)] Straight-chain paraffin hydrocarbons are converted into branched chain olefines having the same number of carbon atoms by subjection to a temperature of 600-1100‹F. at atmospheric pressure for 5 to 200 seconds in the presence of aluminium oxide or aluminium silicate in porous form, e.g. bauxite, clay or kaolin, alone or on a carrier such as silica gel or earthenware, or in the presence of phosphoric acid on silica gel. The aluminium catalysts may be activated by treatment with a mineral acid, e.g. phosphoric, boric or hydrofluoric acid, or with a Friedel-Crafts catalyst, e.g. aluminium chloride or iron chloride. The efficiency of the process may also be improved by the addition of dehydrogenation catalysts, such as oxides or sulphides of molybdenum, tungsten and chromium. The branched chain olefines produced may be removed from the reaction product, and the unconverted paraffins recycled for further treatment. The treatment of n-butane, a mixture of n-butane and isobutane, and of a refinery C4-cut containing butane and isobutylene is described in examples. In the latter case, the isobutylene is first removed, for example by absorption in sulphuric acid. A layout of plant for treating a butane-butylene cut is described. Specifications 18653/12, [Class 2 (iii)], and 496,676 are referred to.