GB581174A - A process for the synthetic manufacture of hydrocarbon oils - Google Patents

Abstract

Hydrocarbon oils are produced by heating purified water gas (including water gas obtained by complete gasification of coal or a gas obtained by decomposing hydrocarbon gases with steam and/or carbon dioxide) which contains CO and H2 in a ratio between 1 : 1.5 and 2 : 1, in the presence of a cobalt, nickel or iron catalyst at 150-250 DEG C. and atmospheric or increased pressure to give olefinic products and a residual gas which latter is (a) mixed with gaseous or liquid hydrocarbons and treated with CO2 and/or steam at 800-1500 DEG C., or (b) treated with CO2 and/or steam at 800-1500 DEG C. and mixed with water gas and/or water gas previously treated with steam at 400-500 DEG C., or (c) part treated as in (a) and part as in (b), the two parts then being recombined, the resultant gas then being subjected to a second synthesis in the presence of a cobalt, nickel or iron catalyst at 150-250 DEG C. to yield further olefines and a second residual gas. This may be treated similarly and the process repeated until the inert gas content renders it useless. The treatment with CO2 and/or steam may be in the presence of a catalyst and CO2 may be wholly or in part removed from the mixture of residual gas and hydrocarbons in (a) or from the water gas or water gas treated with steam in (b). In an example, the synthesis gas containing 41 per cent CO and 51 per cent H2 is treated with a cobalt catalyst at 180 DEG C., the residual gas being mixed with coke oven gas and heated with steam at 1000 DEG C. in presence of a nickel catalyst to produce a gas for the second synthesis stage. The residual gas after removal of CO2 is further treated until five synthesis stages have been effected. The initial synthesis gas may be made partly from coke and partly by decomposition of coke oven gas with CO2. An example is also given in which the synthesis gas is made by treating natural gas with steam.