Verfahren zur Herstellung von wasserstoffhaltigem Spaltgas

摘要

1,135,178. Hydrogen - containing gas mixtures. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. 15 March, 1967 [17 March, 1966], No. 12096/67. Addition to 1,011,696. Heading C5E. A process for the preparation of hydrogen or hydrogen-containing gas mixtures comprises steam conversion of hydrocarbons and/or organic sulphur compounds in the presence of a rhenium catalyst supported on a carrier and in the presence of an alkaline compound. The latter may be a lithium, sodium or potassium compound such as the hydroxide and/or carbonate in an amount less than 1% by weight alkali metal, calculated as alkali metal on carrier, or it may be an amine or ammonia added as such or formed in situ. The carrier is preferably alumina containing not more than 5% by weight silica. Rhenium may constitute 1-25% by weight of the catalyst as the metal, oxide, or preferably sulphide, and may be promoted by Ag, Ni, Co, or Cu. The catalyst may be used as a fixed or fluidized bed and may be regenerated with oxygen and steam at 400-500‹ C. The feed may be a single hydrocarbon, a mixture, or an oil fraction boiling below 200‹ C., and preferably contains 0À01- 10% by weight sulphur; alternatively it may be a sulphur compound such as benzothiophene which is converted to toluene and thence to benzene. Specified feeds include toluene, xylenes, ethyl benzene, or higher alkylbenzenes which, if recycled, can be fully de-alkylated to benzene, carbon dioxide and hydrogen, the hydrogen produced being sufficient to further reduce the benzene to cyclohexane if desired; tops fractions which yield butane, propane and hydrogen as well as methane and ethane; and naphtha boiling between 120‹ and 160‹ C. which yields H 2 , CQ 2 ' and C 1 -C 4 compounds (unspecified). The conversion is operated at 400-800‹ C. with 1-40 moles steam per mole feed, optionally in the presence of added oxygen, e.g. as air, and preferably with a pressure greater than 5 kg/cm.2 and may be directed to produce primarily either a hydrogencontaining gas or a hydrocarbon product.