GB836104A - Fuel composition - Google Patents

Abstract

A fuel composition comprises 10 to 90% by weight of a component A which is one or more hydrocarbons having not more than 2 double bonds and not more than 2 carbocyclic rings per molecule, and 10 to 90% by weight of a component B which is one or more poly-cyclic hydrocarbons having not more than 3 double bonds and having 3 to 6 carbocyclic rings per molecule, the composition boiling in the combined gasoline-kerosene-gas oil range. Component A may be obtained by separating an aromatic concentrate from a gas oil, subjecting it to desulphurizing hydrogenation, followed by a second hydrogenation to reduce the aromatic content to below 10% by weight, and then distilling to obtain a fraction boiling in the range 160 DEG to 320 DEG C. Component A may be a dicyclohexyl alkane which may be substituted with alkyl radicals. Component B may be 1,4-methano cyclohexane, dimethano dihydronaphthalene, dimethano decalin or trimethano tetrahydroanthracene. Lists of suitable compounds for components A and B are given. In examples fuels contain dodecanes, dicyclohexyl propane, kerosene, cis decalin, dimethano decalin, trimethano perhydroanthracene and binortricyclene. In preparing component A the aromatic concentrate is separated from a thermally or catalytically cracked gas oil, or a gas oil obtained by coking a residue from a catalytically or thermally cracking operation, by solvent extraction, for example with aniline, sulphur dioxide, nitrobenzene or furfural. The desulphurization is carried out using as catalyst either a mixture of molybdenum oxide, zinc oxide and magnesium oxide, or molybdenum sulphides, or or tungsten sulphides on activated clay, or iron sulphides on activated bentonitic clay. The desulphurization is carried out at 315 DEG to 485 DEG C., at a pressure of 50 to 285 kg./cm2, at a feed rate of aromatic concentrate of 0.5 to 4 volumes per volume of catalyst, and a feed rate of hydrogen of 280 to 5600 m.3 per m.3 of concentrate.ALSO:A mixture of hydrocarbons having not more than 2 double bonds and not more than 2 carbocyclic rings per molecule, is prepared by isolating an aromatic concentrate from a gas oil fraction, subjecting it to desulphurizing hydrogenation, and then to a second hydrogenation to reduce the aromatic content to below 10% by weight, and distilling to obtain a fraction boiling between 160 DEG C. and 320 DEG C. The gas oil fraction may be a thermally or catalytically cracked gas oil, or may be a gas oil obtained by coking a residue from a catalytically or thermally cracking operation. The second hydrogenation is carried out using a metal or oxide of Group VIII of the Periodic Table as catalyst, at a temperature of 145 DEG to 375 DEG C. and a pressure of 35 to 352 kg/cm.2. 1,4-Methane cyclohexane is prepared by reacting acetylene with cyclopentadiene and hydrogenating the 1,4-methanocyclohexadiene so formed. Dimethano dihydronaphthalene is formed by reacting 1,4-methano cyclohexadiene with cyclopentadiene, and dimethano decalin is formed by hydrogenating dimethano dihydronaphthalene. Trimethano tetrahydroanthracene is formed by reacting cyclopentadiene with dimethano dihydronaphthalene.