Abstract: A fuel composition containing a major amount of a fuel suitable for use in a compression-ignition engine is disclosed. The fuel contains one or more hydrocarbon components boiling within the diesel boiling range, at least one of which hydrocarbon components has been treated with a metal adsorbing or absorbing material in a different physical phase from the hydrocarbon component(s), preferably to reduce the level of at least one metal, more preferably the level of at least one heavier metal, most preferably the level of zinc, in said at least one hydrocarbon component. The emission of NOx, and optionally particulates, is reduced from the exhaust of a compression-ignition engine when such fuel composition is introduced into the combustion chambers. The treatment includes physical separation of the hydrocarbon component from the metal adsorbing or absorbing phase.

Abstract: A fuel composition containing a major amount of a fuel suitable for use in a compression-ignition engine, which fuel contains one or more hydrocarbon components boiling within the diesel boiling range, at least one of which hydrocarbon components has been treated with a metal adsorbing or absorbing material in a different physical phase from the hydrocarbon component(s), preferably to reduce the level of at least one metal, more preferably the level of at least one heavier metal, most preferably the level of zinc, in said at least one hydrocarbon component, said treatment including physical separation of the hydrocarbon component from the metal adsorbing or absorbing phase, is used to operate a compression-ignition engine, and/or a vehicle which is driven by a compression-ignition engine, for the purpose of reducing subsequent formation of deposits, preferably combustion related deposits, during engine operation in the compression-ignition engine into which the fuel composition is introduced and/or of removin

Abstract: Use of a viscosity increasing component (ii) in provided in a composition (i) of a diesel fuel for the purpose of: improving the vehicle tractive effort (VTE) and/or acceleration performance of a compression ignition engine or a vehicle powered by such an engine, into which engine the composition (i) is introduced, or mitigating decrease in the vehicle tractive effort (VTE) and/or acceleration performance, in the case of a diesel fuel composition (i) to which an additional component (iii) is introduced for the purpose of improving the emissions performance, of a compression ignition engine or a vehicle powered by such an engine, into which engine the composition (i) is introduced.

Abstract: The use of an effective concentration of a hydrocarbyl amine wherein the hydrocarbyl moiety has a number average molecular weight in the range 140 to 255 as an additive in an unleaded gasoline composition is provided containing a major proportion of a gasoline suitable for use in a spark ignition engine, for reducing injector nozzle fouling in a direct injection spark ignition engine. A method of operating a direct injection spark ignition engine is also provided.