Abstract

This article reviews the fundamentals of thecatalytic reaction of soot and NO in diesel exhaust to formN2 and CO2 focussing on the model catalyst Fe2O3. It wasfound out that the soot/NO reaction is a side reaction ofthe soot/O2 conversion, in which the Fe2O3 catalyst acts asoxygen pump transferring oxygen from the gas-phase via itssurface to the soot. However, the catalyst is not directlyinvolved in the soot/NO reaction other than increasing thenumber of C* sites. These sites were considered to beresponsible for the NO reduction on the soot facilitating thedissociation of NO and formation of N2. Based on thismechanism a global-kinetic model was constructed.