Shielded Sliding Discharge-Assisted Hydrocarbon Selective Catalytic Reduction of NOx over Ag/Al2O3 Catalysts Using Diesel as a Reductant

The nonthermal plasma generated in a shielded sliding discharge reactor was used to reform diesel for the hydrocarbon-selective catalytic reduction (HC-SCR) of NO x on Ag/Al 2 O 3 catalysts. Compared with raw diesel, the reformed diesel enhanced the NO x reduction efficiency, mitigated hydrocarbon poisoning of the catalyst and reduced the fuel penalty for the HC-SCR reaction. The NO x conversion values obtained with a commercial Ag/Al 2 O 3 catalyst exceeded that of a 2.0 wt% Ag/Al 2 O 3 catalyst prepared by wet impregnation. A significant amount of NH 3 was produced as a by-product during the HC-SCR reaction, which suggests that further NO x conversion enhancement can be achieved by placing a second NH 3 -SCR catalyst in series with the Ag/Al 2 O 3 catalyst.