Potassium dispersed on spinel oxides as catalysts for direct NOx decomposition

摘要

Active catalysts for the treatment of a low temperature exhaust gas stream are provided containing potassium (K) dispersed on a spinel oxide for the direct, lean removal of nitrogen oxides from the exhaust gas stream. The low temperature (from about 400° C. to about 650° C.), direct decomposition is accomplished without the need of a reductant molecule. In one example, K may be dispersed on a surface of a metal oxide support, such as NiFe₂O₄ spinel oxide, synthesized using wet impregnation techniques. The K/NiFe₂O₄ catalyst system converts nitric oxide to nitrogen gas with high product specificity, up to 100%, avoiding the production of a significant concentration of the undesirable N₂O product.