System for fueling and feeding chemicals to internal combustion engines for NO.sub.x reduction

Abstract

Diesel and other lean-burn engines emit less NO.sub.x, when the of fuel comprises an emulsion of hydrocarbon fuel and an aqueous solution of a nitrogenous NO.sub.x -reducing reagent which is separated into its two principal portions prior to combustion. The hot exhaust gases produced by burning the fuel contain NO.sub.x, but the NO.sub.x is reduced by introducing the separated aqueous solution of nitrogenous NO.sub.x -reducing reagent into at least a portion of the exhaust gases and directing them to a catalyst for selective catalytic reduction of NO.sub.x. The fuel emulsion preferably comprises a continuous phase comprising diesel fuel and from about 1 to about 20% (most preferably, from about 2 to about 10%) of a discontinuous phase comprising an aqueous solution of nitrogenous NO.sub.x -reducing reagent. It is also preferred to include in the fuel a corrosion inhibitor and biocide, and optionally a lubricity additive and emulsifier.

Dependencies are inferred from the claim text.