GB513674A - Improvements relating to the production of hydrocarbon motor fuel - Google Patents

Abstract

513,674. Cracking hydrocarbons; carbon monoxide. PROCESS MANAGEMENT CO., Inc. Jan. 5, 1938, Nos. 346 and 347. Convention dates, Jan. 6, 1937, and Oct. 30, 1937. Drawings to Specification. [Classes 1 (ii) and 32] [Also in Group IV] Carbon monoxide and hydrogen are converted into normally liquid and normally gaseous hydrocarbons, the liquid hydrocarbons are admixed with gaseous hydrocarbons containing two or more carbon atoms, and the mixture maintained at 750-1,500‹F. to produce motor fuel of high anti-knock value. Gaseous hydrocarbons, mainly of the C3 and C4 kind may first be heated to promote cracking and conversion to higher hydrocarbons and then admixed and heated with the carbon monoxidehydrogen reaction products, or the admixture may be effected with the gases at a temperature below that at which conversion occurs. The initial heating of the gases may be effected at high temperature and low pressure whereby aromatics are formed, or at.high pressure and low temperature, whereby conversion to aliphatics predominates. The products of the process are fractionated to separate at C3-C4 fraction, and the remaining gases, containing methane and C2 hydrocarbons may be used to produce the carbon monoxide-hydrogen mixture by catalytic oxidation. Preferably a gasoline fraction is separated from the carbon monoxide-hydrogen reaction products and subjected to a temperature of 750-1,500‹F. and elevated pressure in the presence of C3-C4 hydrocarbons produced in the process. Hydrocarbon gases, mainly methane and C2 hydrocarbons are mixed with oxygen and passed to a catalytic chamber containing tubes arranged in parallel between headers and filled with nickel oxide and thoria on fireclay or magnesia at 900-1,500‹F. The products may be purified and the ratio of carbon monoxide to hydrogen adjusted, and pass to one or more synthesis chambers, the tubes of which may be of elongated rectangular cross-section filled with cobalt, thoria and kieselguhr, maintained at 365-415‹F. by, for example, oil cooling. Liquid products and any desired gaseous hydrocarbons are removed after each chamber. The total products are fractionated to separate an overhead containing not more than a small proportion boiling above the gasoline range. This is further fractionated to separate for further treatment a fraction which generally includes all constituents of motor fuel range and, if desired, C3 and C4 gases, but may contain only products boiling at and above 300‹F. The uncondensed portion may be fractionated to remove any gasoline fractions C3 and C4 and part of the C2 hydrocarbons, the remainder being fed to the initial oxidation chamber. The fraction separated for further treatment is admixed before or during the heating thereof to 750-1,500‹F., e.g., 1,050‹F. at 400-3,000 lb./sq. in. with gaseous hydrocarbons of 2 or 3 more carbon atoms obtained as described below. The heating is effected in a coil comprising a pre-heating, a radiant-heating, and a soaking section. The product is treated to separate a stabilized gasoline, which may be blended with that produced earlier in the process, a mainly C3-C4 fraction which is used as the source of hydrocarbons for heating with the liquid carbon-monoxide-hydrogen reaction product, and gases containing 2 carbon atoms or less which may be fed to the initial oxidation stage. A modification is described in which all or part of the liquid products and, if desired, C3-C4 hydrocarbons obtained from carbon monoxide and hydrogen, are admixed with gaseous C3-C4 and if desired C2 hydrocarbons which have been prepared, e.g., at 750-1,100‹F. and 750-3,000 lb./sq. in. or at 1,200-1,500‹F. and 0-200 lb./sq. in., the mixture being maintained at 750-1,500‹F. to effect the desired conversion. Specification 406,326 is referred to.