Fundamental Aspects of Lean-Burn Hydrocarbon Selective Catalytic Reduction
Robbie Burch, Queens University Belfast
The direct reduction of nitrogen oxides by hydrocarbons under lean-burn conditions is still an important target because of the inherent simplicity of the process as compared to NOx storage systems. This presentation will give an overview of our understanding of NOx reduction on noble metal catalysts by a range of hydrocarbons particularly at the lower temperatures found in some diesel emission systems. The dramatic effect of hydrogen as a co-reductant for hydrocarbon SCR with silver catalysts will be described. The lecture will attempt show how we can begin to identify the relevant reaction mechanisms from the interpretation of fast transient kinetic and isotope labelling experiments, combined with density functional theory calculations of some relevant molecular transformations on metal surfaces.