Abstract
The catalytic removal of soot and NOx from Diesel-engine exhausts has been studied by combining laboratory and powerbench experiments. It is concluded that the elimination of both pollutants could be carried out with a three-step catalytic system: 1st) a soot trap loaded with a Pt/CeO2 catalyst, which allows trap regeneration around 500ºC (the role of this catalyst is to oxidise NO to NO2 , and the catalytic activity depends on the BET surface area of the cerium oxide); 2nd) a Pt catalysts for the Selective Catalytic Reduction of NOx by C3H6 operating at 225−325ºC and 3rd) a Rh/CeO2 catalyst for N2O decomposition.