Provided are automated systems and methods for measuring the physical properties of fuels in large storage tanks, and for blending butane into the fuels, including chemometric methods for controlling physical properties selected from volatility, butane content, and density of the fuel during the blending process.

The use of nitrogen-containing compounds as additives in a diesel fuel composition to reduce the impact of deposits in the post combustion system of a diesel engine when combusting said diesel fuel composition. The nitrogen-containing compounds comprise at least 4% by mass of nitrogen atoms and in some embodiments fewer than five NH bonds.

The use of nitrogen-containing compounds as additives in a diesel fuel composition reduce the impact of deposits in the exhaust gas recirculation system of a diesel engine when combusting said diesel fuel composition. The nitrogen-containing compounds include at least 4% by mass of nitrogen atoms and in some embodiments fewer than five NH bonds.

The present disclosure provides fuel additives including Mannich detergent additive(s) and Mannich-based quaternary ammonium salt detergent additive(s) effective to improve engine performance in both port fuel injected and gasoline direct injection engines.

Fuel composition comprising: (i) a base fuel suitable for use in an internal combustion engine; and (ii) a blend of a first monoalkyl alkenyl succinate and a second monoalkyl alkenyl succinate wherein the first monoalkyl alkenyl succinate and the second monoalkyl alkenyl succinate each have the formula (I) or (II) below, or are an isomeric mixture of formula (I) and (II) below: ##STR00001## where R is a linear or branched alkenyl group containing from 4 to 30 carbon atoms, and R.sup.1 is a linear or branched C.sub.1 to C.sub.8 alkyl group; and wherein the first monoalkyl alkenyl succinate is different from the second monoalkyl alkenyl succinate. The fuel compositions of the present invention have been found to provide a synergistic reduction in engine wear.

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.

An unleaded gasoline fuel composition for improving engine performance in spark ignition internal combustion engines comprises: a major amount of gasoline base fuel, and a detergent additive package, wherein the detergent additive package comprises a quaternary ammonium internal salt detergent and a Mannich base detergent mixture, wherein the quaternary ammonium internal salt is obtained from amines or polyamines that is substantially devoid of any free anion species, wherein the Mannich base detergent mixture comprises a first Mannich base detergent component derived from a di- or polyamine and a second Mannich base detergent component derived from a monoamine, wherein the weight ratio of the first Mannich base detergent to the second Mannich base detergent mixture ranges from about 1:6 to about 3:1, and wherein the weight ratio of the quaternary ammonium internal salt detergent and the Mannich base detergent mixture ranges from about 1:10 to about 1:100.

A diesel fuel additive includes a cetane number improver and an at least one organometallic combustion catalyst in solution and/or at least one metal-oxide combustion catalyst in suspension.

The present disclosure provides fuel additives including Mannich detergent additive(s) and succinimide detergent additive(s) effective to improve engine performance in both port fuel injected and gasoline direct injection engines.