Advances in catalytic removal of NOx under lean-burn conditions

The catalytic removal of NOx under lean conditions is one of the most important targets in catalysis research. The activities of metal oxides, zeolite-based catalysts and noble metal catalysts together with the factors are influencing the selective reduction of NOx with hydrocarbons are reviewed. The reaction mechanisms for the three types ofcatalysts are briefly discussed. Recent progress in combined catalyst and NOx storage reduction catalysts is also introduced. Finally, future research directions are forecasted.