Progress in Sulfur Poisoning Resistance of Lean NOx Catalysts

A new concept for a lean NOx catalyst with high resistance to poisoning by sulfur has been proposed. This concept was based on results from an analysis of the mechanism of sulfur poisoning. For substantiation of this idea, a front; Cu/ZSM-5 catalyst and a rear; Au-Pt/TiO₂ catalyst were designed, prepared, and tested on a laboratory scale. This two-stage catalyst confirmed the possibility of recovering activity for lean NOx catalysis in the presence of sulfur.