Patent ID: 6994830

Claim:
A method of treating gases which contain nitrogen oxides, carbonaceous particulates hydrocarbons, and other residual constituents, which method comprises passing the gases through a reactor comprising at least one bed of active material in an enclosure having gas flow conduits for directing gas flow through or over the bed of active material, applying an electrical potential to generate a non-thermal plasma in gas permeating the active material, at least a component of the active material being such as to adsorb or trap carbonaceous particulates, the electrical potential being applied to generate said non-thermal plasma during passage through the active material of the gases undergoing treatment and the component of active material is so as to selectively adsorb or trap carbonaceous particulates and the gases are further subjected to the action of a NO selective catalyst comprising silver doped alumina which selectively absorbs both NO and hydrocarbons and/or partially oxygenated hydrocarbons and promotes their reaction together to reduce NO directly to N 2 .