Method to reduce the ignition temperature of soot being accumulated on a particulate trap

摘要

A method for lowering the ignition temperature of soot accumulated on a particulate filter 2 installed in exhaust tract 1 of an internal combustion engine is described. In this method, a precursor of a catalyst which lowers the oxidation temperature of soot is introduced into exhaust tract 1 downstream from the internal combustion engine and upstream from particulate filter 2. The precursor introduced into exhaust tract 1 is converted to its gaseous phase within exhaust tract 1 prior to contacting the soot accumulated on particulate filter 2. The gaseous catalyst precursor is adsorbed by the soot accumulated on particulate filter 2. Subsequently the catalyst responsible for lowering the ignition temperature is formed from the gaseous precursor in a reaction with at least one other component contained in the exhaust gas flow.