Patent GB-589915-A (GB)
Title: Process for producing mono-olefins from more highly unsaturated hydrocarbons
IPC: C07C9/00
Filed: 1944-11-07
Abstract: A mono-olefin is produced from a more unsaturated hydrocarbon having at least four aliphatic unsaturated carbon atoms and at least one olefinic bond by treatment with hydrogen in the presence of a nickel sulphide catalyst under atmospheric or increased pressure at 150-350 DEG C. (see Group IV).  Nickel sulphide in pellet or other form, with or without binders, activators or stabilizers, or on supports such as silica, alumina or clays, or mixed with tungsten or molybdenum sulphides may be used.  Suspended or fluidized catalysts may be employed.  Nickel nitrate or formate on an alumina or majolica carrier may be decomposed by heating and treated with H2S at about 400 DEG C.  An excess of hydrogen is preferably used, for example 5-15 times the theoretical amount.  A small amount of sulphur, preferably as a compound thereof, may be added to preserve the selectivity of the catalyst during use. Catalysts are regenerated by burning off deposits in air, and re-treating with sulphurous gases if required.  The Specification as open to inspection under Sect. 91 comprises the selective hydrogenation of any unsaturated compound having at least four non-aromatic unsaturated carbon atoms to the corresponding mono-olefinic compound, using hydrogenation catalysts such as metals of Groups 6 and 8, e.g. Ni, Pt, W, and Mo, either free or combined, e.g. as sulphides, under suitable reaction conditions. This subject-matter does not appear in the Specification as accepted.ALSO:A mono-olefin is produced from a more unsaturated hydrocarbon having at least four aliphatic unsaturated carbon atoms and at least one olefinic bond by treatment with hydrogen in the presence of a nickel sulphide catalyst under atmospheric or increased pressure at 150-350 DEG  C. with a liquid hourly space velocity of said hydrocarbon of 0.5-12.  Mixtures of mono-olefins with the corresponding diolefins may be hydrogenated and the mono-olefins used to alkylate hydrocarbons such as isobutane, isopentane, benzene, naphthalene or toluene, or such compounds as phenols, ketones, ethers and esters with an increase in the life of the alkylation catalyst. The initial mixtures may be products of cracking or, for example, a C5 by-product from butadiene manufacture.  Such a by-product containing 57 per cent of diolefins and 43 per cent of mono-olefins is preferably hydrogenated using nickel sulphide on alumina or a mixture of nickel and tungsten sulphides, at 200-300 DEG  C., 1-10 atmos., and a space velocity of 1-5.  Nickel sulphide in pellet or other form, with or without binders, activators or stabilizers, or on supports such as silica, alumina or clays, or mixed with tungsten or molybdenum sulphides may be used.  Suspended or fluidized catalysts may be employed.  Nickel nitrate or formate on an alumina or majolica carrier may be decomposed by heating and treated with H2S at about 400 DEG  C.  An excess of hydrogen is p  preferably used, for example 5-15 times the theoretical amount. A small amount of sulphur, preferably as a compound thereof, may be added to preserve the selectivity of the catalyst during use. Catalysts are regenerated by burning off deposits in air, and re-treating with sulphurous gases if required.  Diolefin hydrogenation may be effected until less than 1-5 per cent by volume remains, the product then being treated in a separate hydrogenation step, by polymerization with acid-treated clay at 200-350 DEG  C., 60-70 per cent sulphuric acid at 30-50 DEG  C. or solid phosphoric acid or other catalysts, with solvents or by extractive distillation to remove the residual diolefin.  The mono-olefin obtained may be used for alkylation with liquid catalysts such as sulphuric acid, hydrogen fluoride or halide organic complexes, for example as described in Specification 540,824, or solid catalysts such as halides.  Initial hydrocarbons specified as being convertible to the corresponding mono-olefins include hexadienes, isoprene, piperylene, cyclohexadiene, methyl cyclohexadiene, dipentene, terpinene and vinyl acetylene.  In examples: (1) a cracked C5 fraction is selectively hydrogenated using various nickel sulphide on alumina or majolica catalysts to give substantially complete conversion of dienes to mono-olefines; (2) a mixture of butanes, butenes and 1,3-butadiene gives almost exclusive hydrogenation of butadiene to b -butylene. Isoprene and piperylene also take up hydrogen mainly in the 1-, 4-positions; (3) a mixture of trimethylcyclohexadienes obtained by hydrogenating isophorone and dehydrating is selectively hydrogenated, using a catalyst prepared by reacting nickel oxide on g -alumina with H2S, to yield trimethylcyclohexenes; (4) a cracked C5 fraction is hydrogenated using nickel sulphide on activated alumina to give an alkylation feedstock of higher mono-olefin content.  The Specification as open to inspection under Sect. 91 comprises the selective hydrogenation of any unsaturated compound having at least four non-aromatic unsaturated carbon atoms to the corresponding mono-olefinic compound, using hydrogenation catalysts such as metals of Groups 6 and 8, e.g. Ni, Pt, W and Mo, either free or combined, e.g. as sulphides, under suitable reaction conditions.  With more active catalysts such as nickel, not more than twice the theoretical amount of hydrogen should be used.  Nickel catalysts may be used in vapour phase hydrogenation at, for example, 75-250 DEG  C., and in liquid phase at 20-200 DEG C. When using catalysts subject to poisoning, feedstocks are first treated for sulphur removal, for example by a preliminary hydrogenation with oxides or sulphides of metals of Groups 4 to 6. Compounds which may be subjected to the hydrogenation include polyolefinic acids, alcohols, esters, ethers, ketones, aldehydes, amines, nitro-compounds, halides, sulphides and mercaptans.  Thus, the unsaturation of drying oils may be reduced, sorbic acid converted to 3-hexenoic acid, geraniol to decylenol and phorone to isobutenyl isobutyl ketone.  Butadienyl acetate may also be used.  Aromatic and heterocyclic groups may be present. Additional examples describe the treatment of hydrocarbon C4 or C5 fractions with nickel-majolica catalysts at temperatures from 95 DEG  to 103 DEG  C.  The treated fractions are used to alkylate isobutane.  This subject-matter does not appear in the Specification as accepted.