GB782853A - Improvements in or relating to fuel compositions - Google Patents

Abstract

Fuel oil blends comprise middle distillate petroleum fractions boiling between 200 DEG and 1000 DEG F. and from 0.01 to 0.5 per cent by weight of natural petroleum resins. The oil may have a boiling range between 300 DEG and 750 DEG F., such as a Diesel oil for automotive or marine purposes, or a heating oil, and may contain between 0.1 per cent and 0.5 per cent by weight of a petroleum resin with a viscosity of from 500 to 1500 S.U.S. at 210 DEG F., or 6000 to 22,000 S.U.S. at 210 DEG F. The resin, such as one obtained from a paraffinic non-asphaltic petroleum crude, may be added directly to the fuel oil, or the resin, such as one obtained from a mixed-base petroleum crude, may be incorporated in the form of residuum obtained from the mixed base crude. The resin or resin-containing residuum maybe decolorized, such as with activated charcoal, carbon black, fuller's earth, montmorillanite or other active clay, before being added to the oil. The petroleum resin may be obtained from an oil, e.g. a residuum, by a two-stage precipitation process. The oil is first contacted with a paraffinic hydrocarbon boiling between 0 DEG C. and 100 DEG C. e.g. a pentane, to precipitate asphaltenes, which are removed, and then with a mixture of a paraffinic hydrocarbon boiling between 0 DEG and 100 DEG C. and either a C1-C4 alcohol, such as n-propyl alcohol, or a C3-C5 ketone or the C1-C4 ester of a C1-C4 carboxylic acid, such as methyl acetate, to precipitate the resin. The oil may also contain amyl nitrate, isopropyl nitrate, methacrylates, b -diethylaminoethylmethacrylate, sodium sulphonates and alkaline earth metal salts of alkyl phenol sulphides.