The invention relates to a microemulsion comprising water in an amount of 1-30 w %; sodium or potassium oleate, Na/K salts of tall oil fatty acid, and/or Na/K salts of C16-C18 saturated or unsaturated fatty acids in an amount of 10-40 w %; oleic acid, tall oil fatty acid, or C16-C18 saturated or unsaturated fatty acids in an amount of 2-40 w %; ethanol in an amount of 0-40 w %; glycerol in an amount of 5-40 w %; and liquid hydrocarbon(s) in an amount of 5-40 w %, up to a maximum or total of components parts of 100 w %. Moreover, methods of manufacture and uses of the microemulsion are disclosed.

A method of producing a nanoemulsion is disclosed that provides an oleaginous base fuel, and water in an amount of at least 10 wt %. A first nonionic surfactant, a second nonionic surfactant and a third nonionic surfactant are mixed in substantially equal weight ratios into a surfactant mixture. The surfactant mixture is mixed with the water and the base fuel to form the nanoemulsion fuel. A nanoemulsion fuel composition can comprise an external oleaginous phase comprised of base fuel, an internal aqueous phase comprised of water, and a surfactant mixture comprised of a plurality of surfactants. The first surfactant can be derived from ethylene oxide, the second surfactant and the third surfactant are detergents having a fatty acid.

Method for reducing intake valve deposits in a spark ignition internal combustion engine which is fuelled with a gasoline fuel composition, wherein the method comprises introducing into the engine an aqueous based composition, wherein the aqueous based composition comprises (i) water, (ii) from 0 vol % to 40 vol % freezing point suppression agent, (iii) from 0 vol % to 10 vol % of surfactant, and (iv) an amine compound in a blending amount of from 0 ppmw to 1000 ppmw.

A process for producing a microemulsion or nanoemulsion comprising water and at least one hydrocarbon or oil, comprising the steps of: a) providing the hydrocarbon or oil, water, one or more additives, a solvent, and a hydrophilic surfactant formulation comprising an amine or amide derivative non-ionic surfactant which is a fatty acid alkanolamide, one or more ethoxylated alcohols and/or ethoxylated alkylphenols, and a non-ionic fatty acid ester; b) by a mixing or stirring device operating at a mixing or stirring speed in the range 100 rpm and 15000 rpm, mixing or stirring the hydrophilic surfactant formulation and additive into the solvent, to produce a hydrophilic self-emulsifying blend; c) adding water to the hydrophilic self-emulsifying blend and the hydrocarbon or oil to produce a water-in-hydrocarbon/oil microemulsion or nanoemulsion, wherein the microemulsion or nanoemulsion comprises: 46% or more by mass of the hydrocarbon or oil, 4% to 36% by mass of water, a mass ratio of hydrophilic surfactant formulation to water in the range 1:10 to 1:2, 0.1% to 5% by mass of additive, 1.2% or more by mass of the solvent, a dispersed particle size in the range 1 nm to 500 nm, and a polydispersity index of 35% PdI or less, wherein the percentages by mass of the hydrocarbon or oil, water, formulation, additive and solvent together add up to 100%.

The present disclosure is directed to a composition and method for producing a nanoemulsion comprising fuel and water. The composition and method can produce a transparent and stable water in fuel nanoemulsion. The disclosure is directed to various surfactants and water contents that may be usable to improve fuel efficiency and reduced carbon emissions that plague known fuels.

There is provided an emulsifier comprising at least one C.sub.8 to C.sub.18 fatty acid diethanolamide, at least one C.sub.12 to C.sub.24 fatty acid, at least one C.sub.6 to C.sub.18 alcohol ethoxylate and optionally at least one sorbitan ester and/or at least one alkylene glycol monoalkyl ether. There is additionally provided emulsions comprising a fuel, water and an emulsifier and methods of producing emulsions.

A fuel composition for use in internal-combustion engines has a fuel component, an alcohol component, a water component, a microemulsion blend, and a cetane-enhancer component. The microemulsion blend includes at least one of lower grade fatty acid derivatives being present in an amount effective for the fuel, alcohol, and water components to form a microemulsion blend. The emulsifier is present in an amount effective for the biodiesel fuel, alcohol, water, and emulsifier to form an emulsion.

A water in diesel oil fuel micro-emulsion for internal combustion diesel engines, with a low content of surfactants, a very long shelf-life, a reduced production of pollutants and carbonaceous side-products generated by the combustion and very good engine performance, is described. These emulsions comply with the strict requirements of Italian regulations and are particularly useful as fuels for automotive and heating applications.

A fuel composition for use in internal-combustion engines has a fuel component, an alcohol component, a water component, a microemulsion blend, and a cetane-enhancer component. The microemulsion blend includes at least one of lower grade fatty acid derivatives being present in an amount effective for the fuel, alcohol, and water components to form a microemulsion blend. The emulsifier is present in an amount effective for the biodiesel fuel, alcohol, water, and emulsifier to form an emulsion.

There is provided an emulsifier comprising at least one C.sub.8 to C.sub.18 fatty acid diethanolamide, at least one C.sub.12 to C.sub.24 fatty acid, at least one C.sub.6 to C.sub.18 alcohol ethoxylate and optionally at least one sorbitan ester and/or at least one alkylene glycol monoalkyl ether. There is additionally provided emulsions comprising a fuel, water and an emulsifier and methods of producing emulsions.