Several review papers [1–5] report on different types of PrOx catalysts developed and investigated over the last decade by various research teams. These catalysts can be classified into threegroups: (i) supported platinum metal (Pt, Ru, Rh) based catalysts,(ii) supported Au-containing catalysts, (iii) and copper–cerium oxide based catalysts. Although considerable progress has beenmade towards the development of active and selective catalysts,the removal of CO to a level below 10 ppm and the simultaneous