Experimental Study Of Mulriple Oxide Used For Decontaminating PM And No_x Of Diesel Engine

Diesel engine has many advantages compared with gasoline engine, so it has widely used in commercial vehicles, and the application in the passenger vehicle is also improved. The discharge of its pollutants is becoming more and more harmful, so we must develop the purification technology of diesel engine machine. The multiple oxide catalytic purification technology is researched, and delafossite catalyst is less used in vehicle emission control at present.By using solution combustion synthesis method, several Li-Co delafossite catalysts(LiCoO2, Li0.9CoO2, Li0.8CoO2, Li0.7CoO2, LiCo0.9O2, LiCo0.8O2 and LiCo0.7O2) were prepared, and the prepared catalysts were characterized by XRD and SEM. A catalyst micro evaluation system was catalysts, and the purification effect of the catalyst was tested by using simulated gas. Finally, catalysis-assisted non-thermal plasma technique for exhaust gas control was used. The main research results are as follows:(1) The Li-Co delafossite catalysts prepared by using solution combustion synthesis method have typical six partly layered structures of ABO2 delafossite catalysts, and the size distribution of the catalyst particle was uniform. The optimum preparation conditions of the catalysts is that urea excesses 100%, and the heat treatment temperature is 700℃.(2) The purification effect of the prepared catalyst was tested by using simulated gas. The optimum catalyst is LiCo0.9O2, the light-off temperature Tig is 283℃, and the purification rate of NOx could reach 17.8%. The B cation Co affects the catalyst activity, and an appropriate change of the stoichiometry of Co ion can significantly improve the activity of the catalyst.(3) Using TiO2, La2O3, CeO2 and other rare earth metal oxide as catalyst additives can effectively improve the activity of the Li-Co delafossite catalyst. Increasing the catalyst coating times can not only improve the purification effect, but also reduce the catalyst loss after heating reaction.(4) The prepositive non-thermal plasma can significantly improve the purification effect of diesel engine PM and NOx of the catalyst LiCo0.9O2. Under the condition of 30 kV and 50 Hz, the prepositive plasma combined with the catalyst LiCo0.9O2, the purification rate of NOx efficiency up to 25%.