A catalyst of V2O5-WO3-MoO3/TiO2 was prepared from industrial pure chemicals in which ammonium metavanadate was the main active component

ammonium tungstate and ammonium molybdate were active and structure coagents

anatase titanium dioxide was catalyst support.The catalyst could be suitable for the application in various diesel engine working conditions and the complicated exhaust compositions.It was tested on a Lister Petter TR1 type fuel injection single cylinder diesel engine to investigate conversion of NOx and catalytic selectivity.The results show that the NOx conversion declined with the increase of diesel engine loads.As the diesel engine running at 1800 r·min-1

the maximum conversion of NOx was 87.1% at load 25% and at the conditions of SV(space velocity)20000 h-1

reaction temperature 380℃ and NH3:NOx 1.0.For different loads

reaction temperature had greatly effect on NOx conversion.The temperature window(NOx conversion>70%)of the catalyst was 340—440℃ at load 25% and changed to 400—440℃ at load 50%

reducing about 60℃.Increase of diesel engine load could improve initial temperature of NH3/N2O reaction

while it could lead to increase of N2O generated at high temperature(>400℃).