High Temperature Heterogeneous Redox Catalysis for NOx Abatement

This proposed program addresses the high temperature (>500oC) decomposition of nitrogen oxides using redox catalysts based on single phase complex metal oxides with constituents selected for their overall influence on binding of oxygen to the catalyst surface and anticipated ease of rereduction of active sites. Catalysts so selected will also possess long lifetimes arising from dispersion of active species as cations within a single phase ceramic matrix and the overall refractory nature of the catalysts. The catalysts will be applied to exhause streams containing NOx, CO, hydrocarbons and oxygen (from 0 to 20 vol%) as well as water, CO2 and SO2. These streams will be representative of exhausts from fixed and mobile power sources utilizing hydrocarbon fuels. The proposed catalysts will not suffer from problems of hydrothermal instability encountered with zeolite-based redox catalysts and will possess superior activity for not only NOz removal but effectively two-and three-way catalysis as well. Catalysts will possess both hydrogen and oxygen storage capabilities so that application under both net oxidizing and net reducing conditions will be possible.