Technical Paper
On the Development of Low PGM Content Direct Soot Combustion Catalysts for Diesel Particulate Filters
2010-04-12
2010-01-0558
A study of the application of base-metal- and precious-metal-doped base metal direct soot oxidation materials to the remediation of diesel particulate matter has been performed. The study has addressed the impact of reactive gas environment on the de-coupling of catalyst to soot contact, the control of secondary emissions of CO, HC and NOx and the impact of "dilution" of the washcoat by the substrate mass. These studies have confirmed previous findings regarding the toxic effect of NO₂ generation at the catalyst-soot interface but also demonstrate that under ideal circumstances propagation of the exotherm related to CO and (especially) HC light-off can result in an "exotherm cascade" capable of providing soot ignition at T ≺ 250°C.
