A method for the continuous production of an improved diesel fuel, having enhanced ignition characteristics, more particularly with a greater electric conductivity, enhanced cetane numbers and lubricity and with greater percentage of complete combustion, resulting in less soot production and NOx reduction at the same time in an internal combustion diesel engine, breaking the tradeoff in the emission of those two pollutants from an internal combustion diesel engine.

A fuel emulsion for powering a diesel engine contains water, a fuel, and an emulsifier package containing a quaternary ammonium surfactant. A method for powering a diesel engine with the fuel emulsion involves preparing the fuel emulsion by emulsifying a fuel and water in the presence of the emulsifier package. An emulsifier package for emulsifying a fuel and water contains a quaternary ammonium surfactant and at least one nonionic surfactant, which is an alkoxylate. The quaternary ammonium surfactant is obtainable by reacting a quaternizable nitrogen compound containing at least one quaternizable, especially tertiary, amino group with a quaternizing agent, which converts the at least one quaternizable, especially tertiary, amino group to a quaternary ammonium group, where the quaternizing agent is a hydrocarbyl epoxide in combination with a free hydrocarbyl-substituted polycarboxylic acid.

A method for powering a diesel engine with a fuel emulsion involves preparing the fuel emulsion by emulsifying a fuel and water in the presence of an emulsifier package, which contains an anionic surfactant selected from sulfates and sulfonates. The emulsifier package for emulsifying a fuel and water and the fuel emulsion for powering a diesel engine are also provided.