Unique silver/alumina catalysts developed in collaboration with BASF Corporation were investigated at General Motors under simulated lean-burn engine exhaust feed conditions for the selective catalytic reduction of NO
x
using hydrocarbons as reductant (HC-SCR). Catalysts were evaluated using a laboratory fixed-bed flow reactor system over a wide range of temperatures relevant to light-duty and heavy-duty exhaust conditions for CIDI (compression ignition direct injection – diesel) and SIDI (spark ignition direct injection – gasoline) applications. This report investigates the effects of silver content (i.e., wt.% Ag
2
O) and reductant composition (i.e., simulated diesel fuel, simulated gasoline, ethanol, and ethanol/simulated gasoline mixtures) on the steady-state NO
x
reduction activity. A dual catalyst approach using a HC-SCR catalyst followed by an NH
3
-SCR catalyst was also investigated. Stochastic Process Modeling was used to determine the optimum in-exhaust injection strategy using ethanol and simulated gasoline as reductants during the New European Driving Cycle.
Purchase more technical papers and save! With TechSelect,
you decide what SAE Technical Papers you need, when you need them, and how much you want to pay.
Learn more >
