Preparation Of Cobalt-aluminum Catalyst And Its Catalytic Research On Ethylbenzene

In recent years,with the continuous development of the marine transportation industry,the damage to environment by VOCs pollutants produced by ship coating has become more and more serious.Long-term inhalation of these pollutants can cause great damage to people’s health.The main treatment technologies for VOCs include adsorption,condensation,combustion,catalytic oxidation,etc.Among them,the catalytic oxidation method has attracted much attention for its advantages of low energy consumption and high efficiency.The core of catalytic oxidation is catalyst.In view of the high production cost and poor stability of the commonly used novel metal catalysts and metal oxide catalysts in the past,the thesis successfully prepared a Co Al₂O₄ catalyst with a spinel structure.It was modified by the sol-gel method with doping K₂CO₃.At the same time,the optimal preparation method,optimal preparation conditions and optimal evaluation conditions of the catalyst were explored.The catalyst was characterized and analyzed by XRD,SEM,BET,TG,XPS,H₂-TPR,so as to explore the reasons for the high catalytic activity.This thesis mainly conducts research through two aspects,the specific research content is as follows:1.The Co Al₂O₄ catalyst was prepared and evaluated by the sol-gel method,co-precipitation method and reverse co-precipitation method.The study found that the Co Al₂O₄ catalyst prepared by the sol-gel method has the best catalytic activity.Besides,we explored the optimal preparation conditions and optimal evaluation conditions of the catalyst.The preparation conditions mainly include the exploration of the catalyst calcination temperature and calcination time.The evaluation conditions mainly include the gas flow rate during the catalyst test,the catalyst filling quality and the evaluation temperature,etc.The research results show that the catalyst has the best catalytic effect when the catalyst is calcined at 700℃for 4 h.When the gas flow rate is 20 m L/min and the filling quality is 0.2g,the catalyst has better catalytic activity.2.K₂CO₃modifying Co Al₂O₄catalyst was prepared by the sol-gel method（x K₂CO₃/Co Al₂O₄,x=0.05,0.10,0.15,0.20）.The influence of different doping amounts of K₂CO₃ on the adjustment of the catalytic activity of the catalyst was explored.The study found that the doping of K₂CO₃ can be effective to improve the catalytic activity of the Co Al₂O₄spinel catalyst.When the K₂CO₃doping amount is 15%,the catalyst has the best catalytic activity.When the evaluation temperature is 194℃,the conversion rate of the catalyst to ethylbenzene can reach 90%.And the catalyst has a good crystal form,a high specific surface area and an excellent low-temperature H₂-reducibility.