FIELD: spark ignition engines.
SUBSTANCE: invention relates to additives that reduce particulate emissions in spark ignition engines. Proposed is the use of a quaternary ammonium compound as an additive for a gasoline composition to reduce particulate emissions from a direct injection positive ignition engine; wherein the quaternary ammonium compound is a reaction product of a nitrogen compound having at least one tertiary amino group and a quaternizing agent, wherein the nitrogen compound having at least one tertiary amino group can be selected from: (i) the reaction product of a hydrocarbyl-substituted acylating agent and a compound comprising at least one tertiary amino group and a primary amino group, a secondary amino group, or an alcohol group; and (ii) a tertiary amine having the formula R1R2R3N, in which each of R1, R2 and R3 independently represents an alkyl group or a hydroxyalkyl group containing from 1 to 50 carbon atoms; and where the quaternizing agent is selected from a carboxylic acid ester having the formula R5COOR0, alkyl nitrates and epoxides; where R0 represents a C1-C7 alkyl group, and R5 represents the residue of a carboxylic acid selected from a substituted aromatic carboxylic acid, α-hydroxycarboxylic acid and polycarboxylic acid. Also proposed is the use of a quaternary ammonium compound as an additive in a gasoline fuel composition to improve the performance of a particulate filter installed in the exhaust system of a direct injection positive ignition engine.
EFFECT: reduction of particulate emissions from an engine with direct fuel injection and forced ignition.
10 cl, 1 dwg, 2 tbl, 3 ex
