| Air pollution by VOCs has drawn considerable attention in recent years. After "smoke of coal", "photochemical smog" pollution, people are entering the third pollution time-"indoor air pollution". Among the technologies developed for the treatment of VOCs, the catalytic combustion is to be a promising technology. VOCs, especially BTX, are typical pollutants that can lead to cancer, aberrance and mutation. It is difficult to eliminate BTX from atmosphere due to the stability of their molecule structure. Therefore, it is very important to prepare the low light-up temperature and high selectivity catalyst in order to reduce energy cost and avoid the occur of by-product that can lead to twice pollution.In this paper, colloid-precipitation method was used to prepare the colloidal gold supported on ZnO, Co2O3, CeO2, ZrO2, Al2O3 and MgO nano metal oxide catalysts. An evaluating method of the catalytic rule of colloidal gold supported on nano oxides for catalytic decomposition of BTX was proposed. Furthermore, the behavior and influence factor of benzene, toluene and xylene was studied. Colloidal gold supported on nano zinc oxide was chosen as the optimal catalyst for BTX catalytic oxidation. The kinetic mechanism and product analysis of catalytic combustion of BTX was investigated. The main contents and results in this thesis can be summarized as follow:The colloidal gold solution was prepared by chemical reduction reaction with NaBH4. The size of colloidal gold is below 5nm characterized by UV-Vis and TEM. Colloidal gold supported on nanooxide was prepared by colloidal-deposition method. Catalytic activity of colloidal gold supported on nanometal oxide was characterized by self-desighed catalytic oxidation reaction system. The reaction condition of BTX was optimized and the BTX before and after catalytic oxidation was detected by gas chromatography.The catalytic activity of colloidal gold supported nanometal oxide is related to the nature of supports that is the very essential point of high catalytic activity. The catalytic activity of colloidal gold supported nanometal oxide is correlated with the dimension of nanogold particles that is demonstrated by the optimal gold loading experiment. The catalytic activity for BTX oxidation is also related with the structure of BTX molecule. Besides, the structure of xylene can also affect the catalytic activity of the catalyst.It is very important to choose a proper catalyst to degrade BTX including benzene, toluene and xylene at real conditions. Therefore, we operate our catalytic oxidation experiments under a mixture gas of benzene, toluene and xylene in order to distinguish the catalytic activity of all the gold colloidal supported catalysts. Ultimately, we find the gold colloidal supported on nano zinc oxide which is an optimal catalyst for the BTX catalytic oxidation at real conditions.The catalytic combustion kinetics mechanisms of benzene and toluene match well with the Mars-van Krevelen and Langmuir-Hinshelwood kinetic mechanism models. And the kinetics mechanism of xylene is different with the structure of the molecule. The activation energy of benzene is more than that of toluene. It is indicated that the catalytic combustion of benzene is more difficult than that of toluene, while, the experimental data is opposite. So it suggested that something more restrains or promotes the catalytic combustion of toluene or benzene. The product analysis of benzene catalytic combustion shows that the catalyst can make benzene catalytic combustion completely under no by-product and long-term using without activity losing.
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