Study On Catalytic Oxidation Of Typical VOCs By Modified Porous Carbon Materials

The massive emissions of volatile organic compounds?VOCs?pose a serious hazard to human health and the environment.Among the existing treatment methods,the catalytic oxidation method can treat lower concentration VOCs at low temperature,which is a relatively economical and efficient processing technology,but there are still problems such as high light-off temperature or poor stability.Therefore,it is necessary to develop a new type of high performance catalyst.The manganese-ruthenium based catalyst were prepared by ultrasonic assisted equal volume impregnation method.The physicochemical properties were characterized by BET,SEM,XRD,XPS,H₂-TPR and FTIR.Taking toluene as the research object,the effects of preparation conditions and reaction conditions on the performance of the catalyst were studied experimentally.The 2Ce3Mn/CF catalyst was selected and the catalytic oxidation mechanism of toluene was revealed.On the basis of this,the catalytic oxidation characteristics and multi-component VOCs of the preferred catalysts for benzene and chlorobenzene are obtained.The research results of this paper have certain theoretical guiding significance for the development of typical VOCs catalytic oxidants.The results of studies on the preparation conditions and reaction conditions on the activity of the catalyst indicated that the catalyst had the best catalytic performance at a molar ratio of Ce/Mn of 2:3,the loading of active component of 14wt%,a space velocity of 22500 mL·g^-1·h^-1,an oxygen concentration of 20%and an initial toluene concentration of 300 ppm.The conversion of 300 ppm of toluene can reach 90%at 200?.The characterization results show that the series of catalysts are mesoporous materials,and the specific surface area is much higher than that of similar catalysts.The Mn species and Ce species form highly dispersed CeMnOx solid solution,resulting the surface oxygen species and oxygen mobility increase,and finally the catalyst activity was increased.This paper also studied the catalytic performance of the preferred catalyst for benzene,chlorobenzene and multicomponent VOCs.The results showed that the catalytic properties of 2Ce3Mn/CF catalysts for single-component benzene and chlorobenzene at different initial concentrations were poor.The conversion rates of1000 ppm of single-component benzene and single-component chlorobenzene were33%and 45.82%respectively at 350?.In the multi-component VOCs system,the catalytic activity of 2Ce3Mn/CF catalysts for benzene,toluene and chlorobenzene is significantly different.Toluene has a certain inhibitory effect on the adsorption and catalytic oxidation of benzene,and there is competition between it and chlorobenzene.