NOx removal efficiency and N2 selectivity during selective catalytic reduction processes over Al2O3 supported highly cross-linked polyethylene catalysts

Abstract

The performance of a highly cross-linked polyethylene catalyst supported on alumina for low temperature selective catalytic reduction of NOx by unburned hydrocarbons (HCs) existing in an exhaust gas was examined at different engine conditions with the addition of exhaust-gas recirculation. The HXPE catalyst was shown to exhibit good NOx reduction activity at low temperatures (100–250°C) where the only reductant was the unburned HC, which was already present in the exhaust flow. The maximum NOx reduction of approximately 52% was achieved at a temperature of 150°C. HXPE demonstrated very good selectivity toward N2 in the majority of tested conditions (∼80%).