Use of a wax anti-settling agent (WASA), in an automotive fuel composition, for the purpose of improving the acceleration performance of an internal combustion engine into which the fuel composition is or is intended to be introduced or of a vehicle powered by such an engine.

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.

The invention relates to the use of quaternized nitrogen compounds as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems; the invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

Disclosed herein is a method for synthesizing a nano-emulsion fuel composition. The method may include forming a water-in-fossil fuel emulsion by dispersing water into a fossil fuel in the presence of a surfactant, synthesizing carbon quantum dots with an average diameter between 0.5 nanometers to 20 nanometers, forming a mixture of the synthesized carbon quantum dots and the water-in-fossil fuel emulsion by dispersing the synthesized carbon quantum dots into the water-in-fossil fuel emulsion; the carbon quantum dots comprising 1 ppm to 10000 ppm of the mixture, and forming a nano-emulsion fuel composition by mixing a biofuel into the mixture of carbon quantum dots and the water-in-fossil fuel emulsion.

Fouling and/or asphaltene agglomeration (or flocculation) in midstream processes and transportation and in upstream transportation of a hydrocarbon oil is reduced by providing in the oil an additive combination including; (A) a polyalkenyl-substituted carboxylic acid or anhydride, and (B) a metal detergent system comprising a hydrocarbyl-substituted hydroxybenzoate metal salt or a hydrocarbyl-substituted sulfonate metal salt or a mixure of both salts or a complex thereof,
where the mass:mass ratio of (A) to (B) is in the range of 20:1 to 1:20 and the treat rate of the additive is in the range of 5 to 10000 ppm by mass.

A liquid hydrocarbon marine fuel oil includes a marine distillate fuel or a heavy oil or a blend thereof containing an additive combination including: (A) a polyalkenyl-substituted carboxylic acid or anhydride, and (B) a metal hydrocarbyl-substituted hydroxybenzoate and/or sulfonate detergent, where the mass:mass ratio of (A) to (B) is in the range of 20:1 to 1:20 and the treat rate of the additive combination is in the range of 5 to 10000 ppm by mass.

The invention relates to the use of quaternized nitrogen compounds as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems; the invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

Provided are water-based fuel additive compositions that, when combusted with a fuel containing vanadium in a gas turbine, inhibit vanadium hot corrosion in the gas turbine. The water-based fuel additive compositions include at least one rare earth element compound or alkaline earth element compound that retards vanadium corrosion resulting from combustion of vanadium rich fuel.

Provided are oil-based fuel additive compositions that, when combusted with a fuel containing vanadium in a gas turbine, inhibit vanadium hot corrosion in the gas turbine. The oil-based fuel additive compositions include at least one rare earth element compound or alkaline earth element compound that retards vanadium corrosion resulting from combustion of vanadium rich fuel.

A quaternary ammonium salt of formula (I): wherein X is a linking group; Y is O, NH or NR.sup.1 wherein R.sup.1 is H or an optionally substituted hydrocarbyl group; Q.sup.+ is a moiety that includes a quaternary ammonium cation; A.sup. is an anion; R.sup.2 is an optionally substituted alkylene group; R.sup.3 is hydrogen or an optionally substituted hydrocarbyl group; and n is 0 or a positive integer; provided that n is not 0 when R.sup.3 is hydrogen.

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