GB544155A - Improvements in or relating to the catalytic reforming of gasolines and naphtha - Google Patents

Abstract

544,155. Catalytic dehydrogenation and hydrogenation. KELLOGG CO., M. W. Sept. 27, 1940, No. 14648. Convention date, Oct. 3, 1939. [Class 1 (i)] [Also in Group IV] Motor fuels of high anti-knock value containing a high percentage of naphthenic compounds and free from olefines are obtained by passing a naphtha fraction boiling within the gasoline range and consisting mainly of aliphatic hydrocarbons together with hydrogen over a dehydrogenating-aromatising catalysts at temperatures between 800 and 1000‹F., under pressures of 1-30 atmos. and with a space velocity of less than two volumes of liquid naphtha per volume of catalyst whereby the naphtha is converted into aromatic and olefinic hydrocarbons and gases, separating the normally liquid products of the reaction from the gases and passing the liquid products with hydrogen over a hydrogenating catalyst at 200‹F. 20 atmos. pressure, and a space velocity of 0.25 volumes of liquid per volume of catalyst per hour, whereby the aromatic hydrocarbons are hydrogenated to produce naphthenic hydrocarbons and the olefines are hydrogenated to yield saturated compounds. The aromatisation catalyst specified comprises oxides of metals of the 6th Group of the Periodic System together with oxides of metals of the 3rd Group, e.g. catalysts prepared by depositing 10 per cent. chromium oxide on activated alumina or by co-precipitating molybdenum and aluminium oxides. The catalyst used in the second stage is the same as that used in the first stage or catalyst produced by soaking silica gel or pumice in nickel nitrate and then igniting the mixture to convert the nickel to oxide which is reduced to nickel by treatment with hydrogen. Ten per cent. copper may be added to the nickel. Hydrogen from the second stage after purification may be re-cycled to that stage.