Preparation And Application Research Of Catalysts For Wastewater Treatment In Wet Catalytic Oxidation Process

The degradation of organic wastewater has always been the key issues in thefield of water treatment. Contrast to the traditional water treatment process, theadvanced oxidation process （AOPs） can degrade organic compounds and promote thebiodegradability of the wastewater. Most modern chemical oxidation processes, suchas catalytic wet peroxide oxidation （CWPO） presents the advantages of efficient,economic and the moderate experiment conditions in the wastewater treatment. So thedevelopment to improve catalytic efficiency is meaningful.In this work, catalysts have been synthesized under different preparation processusing γ-Al₂O₃as support and using Cu/Fe as active componets. In addition, phenoland β-naphthol have been chosen as target pollutant. In this work, low concentration（original COD=150mg/L）, high concentration（original COD=1500mg/L） and highsalinity（concentration of Na2SO4=3g/L） of effulent have been prepared, and thecatalytic performance have been test in such three conditions.The XPS, XRD and N2adsorption–desorption were employed to characterize thestructure of the catalysts and evaluated the influence of preparation process to thecatalysts strcture. It can be found that the activity temperature of support control thecrystallite size of the catalysts and the crystal form of the Al₂O₃support; And theloading of the metal active componets influenced the specific surface area of catalystshugely; Besides the calcination temperature of the catalysts determined the componetson the surface of the catalysts. Among all the catalysts, sample AT550-5%Cu-CT450（550℃activated γ-Al₂O₃impregnated in5%（wt%） Cu （NO3）2and CO（NH2）2solution for8hours and calcined under450℃for4hours.）presents the features ofhigh SBETvalue and small pore size.A large amount of CWPO experiments have been done in this work, and the theCOD reduction of model wastewater was employed to evaluate the performance ofcatalysts. Through the CWPO experiments, the influence of catalyst preparationprocess to the performance of the catalysts have been studied.In the treatment of low COD（initial COD=150mg/L） effulent by CWPO process, the experiment conditions have been immoblized as50℃of temperture,3of theinitial reaction pH value and the concentration of the catalysts and peroxide was1.25g/L and500mg/L respectively. Using catalyst sample AT550-5%Cu（Fe）-CT450,the COD reduction of the model wastewater was around90%in20min; In thetreatment of high COD（initial COD=1500mg/L） effulent by CWPO process, with theuse of1.25g/L catalyst （sample AT550-5%Cu（Fe）-CT450） and1.5g/L H₂O₂, the CODreduction of the model wastewater was around80%in80min.In addition,3g/L ofNa2SO4was added into model wastewater. And it can be found that the salinity of themodel wastewater do not influence the performance of the catalyst.