Research On Preparation,Modification And Performance Of Cu-based Catalytic Combustion Catalyst

In the 21st century,the economy has developed rapidly,which has led severe damage to the environment.Volatile organic compounds（VOCs）have become one of the main atmosphere pollutants in China.The government has issued a variety of regulations to limit the emissions of VOCs.And the exploration of its removal methods has gradually attracted the attention of researchers.So far,common removal methods mainly include absorption,adsorption membrane separation,biodegradation,high-temperature combustion,catalytic combustion and so on.Among them,the catalytic combustion method has attracted wide attention due to its high removal efficiency,less secondary pollution,and simple operation.However,among the existing catalysts,noble metal catalysts are difficult to industrialize due to their excessive cost.For transition metal catalysts,its removal efficiency needs to be further improved.Therefore,it is urgent to develop a catalyst with high removal efficiency and low cost.Based on this,a series of copper catalysts were prepared by co-precipitation-kneading method with different supports,include Al₂O₃,TiO₂,MgO,SiO₂ and CeO₂,and CuO/Al₂O₃ has the best performance.In addition,the performance of the catalyst still has the potential for improvement.In order to achieve better catalytic activity,the catalyst was modified with cerium doping.When the feed is toluene with a concentration of 1000 ppm,the conversion rate reached 90%at 255°C.A series of characterization methods were carried out to further study the effects of Ce doping.When the doping amount is appropriate,Ce doping can significantly improve the properties of the catalyst,promote the dispersion of surface active components and increase the adsorption of oxygen on the catalytic surface,which is beneficial to catalytic combustion activity.Meanwhile,the prepared catalysts were tested for universality with other substrates,including benzene,xylene,trimethylbenzene,cyclohexane,and n-hexane,all of which achieved complete combustion at lower temperatures.Then the catalyst was tested for stability.After 50 hours of operation under T90,there was no significant decrease in activity,proving its good stability.