Preparation And Applications Of Microporous And Mesoporous Zeolites Catalysts For VOCs Combustion

With the development increasing of industry and technology,the problem of environmental pollution is becoming more and more serious.VOCs pollution is one of the most serious problems on destroying the environment of human being.Catalytic combustion is one of the most effective method to control the content of VOCs in atmosphere for its advantages of high efficiency,low energy cost and complete degradation.It is contributed to enhance the VOCs combustion efficiency by select suitable materials and low energy cost equipment,the paper is focused on the materials and equipment.It has been developed and optimized a new technology to prepare the novel microfibrous Beta zeolite composite,discussing the effect of synthesis time,synthesis temperature,ratio of Si/Al on size and crystallization of it.It's found that the optimized synthesis conditions are:synthesized at 100 ^oC,for 7 days and the ratio of Si/Al is 25 for Beta seed synthesis.It has also been discuss the effect of synthesis time,synthesis temperature,ratio of Si/Al,solvent ratio and solvent kinds on the membrane thickness,texture properties of the composite.The optimized synthesis conditions are synthesizing the composite on 150 ^oC for 6 days,and the ratio of Si/Al is infinity,choosing the n-propyl alcohol as solvent and the solvent ratio is 2.It has been prepared the Cu/Beta/PSSF?Mn/Beta/PSSF?Cu-Mn/Beta/PSSF catalyst by incipient wetness method,and study the catalytic combustion behaviors on them,when the ratio of Cu/Mn=1:3,the catalyst show the best catalytic activity for toluene combustion,And the T₅₀ and T₉₀ were 251 ^oC and 300 ^oC,respectively?It has been prepared Co/ZSM-5/PSSF composite catalyst by incipient wetness method and characterized them by XRD,SEM,N₂ adsorption/desorption methods.It has also design structured fixed bed reactors composed of Co/ZSM-5/PSSF and Co/ZSM5/G,study the catalytic activities of reactor for isopropanol combustion and the bed pressure drop.It's found that the support of ZSM-5/PSSF is benefit to disperse the metal and enhance the activity sides,the membrane on the metal fibers is scale of micrometer,which is benefit to increase diffuse efficiency and enhance heat transfer coefficient.The three-dimension structure of ZSM-5/PSSF is benefit to decrease bed pressure drop.The reactor composed of Co/ZSM-5/PSSF show the best catalytic activity for isopropanol combustion,the T₅₀ and T₉₀are 241 ^oC and 337 ^oC,respectively.It have been prepared Cu,Mn oxides modified MCM-41 catalysts by incipient wetness method and Cu oxides modified MCM-41 catalysts by chemical vapor deposition method.It has been discuss the effect of metal loading and calcined temperature on the textual properties,stability and catalytic activity for toluene combustion of catalyst.The specific surface are and mesoporous volume decrease dramatically by the metal oxides occupying the pore when the metal loading reach 32 wt%,the catalyst prepared by chemical vapor deposition method show a better textual properties than it preared by incipient method.The catalysts are stable for toluene combustion.Mar and Van Krevelen model is suitable to describe the behavior of toluene combustion on catalyst,on the contrary,the Power rae Law model is not.