Preparation,Characterization And Catalytic Oxidation Of Phenol Wastewater From Fe-Ni/CSAC Binary Catalyst

Phenol?C₆H₅OH?is a typical refractory organic wastewater.Conventional processing technologies are focused on physical and chemical processes,and there will be a large number of toxic products during the processing.In the wastewater treatment process,researchers have conducted extensive research due to the advantages of catalyst recovery,no secondary pollution,and strong oxidizing properties due to heterogeneous ozone catalytic oxidation technology.In this experiment,an impregnation method and a co-precipitation method were used to prepare a coconut shell activated carbon?CSAC?supported Fe-Ni catalyst.The effects of Fe/Ni ratio of active components,roasting time,roasting temperature and heating rate on the catalyst activity were investigated.Determine the preliminary preparation conditions by comparing the removal effects of phenol wastewater.Then,the surface methodology?RSM?was used to optimize the preparation conditions to obtain the best preparation conditions.XRD,XPS,BET,SEM and other characterization techniques were used to analyze the surface morphology,pore structure,and element valence of the catalyst to explore the mechanism of catalytic oxidation.The main conclusions are as follows:?1?When Fe/Ni was 0.945,the calcination temperature was 431.885?,the calcination time was 3.677h,and the heating rate was 1?·min^-1,the supported ferric nickel catalyst prepared by co-precipitation method had the best catalytic activity,and the removal rate of phenol was 85.95%.?2?Through characterization analysis,the catalyst surface contained amorphous Fe-Ni and NiFe₂O₄ crystals,the specific surface area of Fe-Ni/CSAC catalyst was502.68m²·g^-1,and the pore diameter was mainly 3.0-4.6nm,which was a mesoporous material.The metallic particles on the surface of the catalyst were relatively uniform without agglomeration.?3?The heterogeneous Fe-Ni/CSAC ozone-catalyzed phenol treatment system was established to determine the optimal reaction conditions.When the concentration of phenol wastewater was 300mg·L^-1,the catalyst dosage was 10g·L^-1,the p H value was 9.96,the reaction temperature was 25?,and the reaction time was 90min,the removal rates of phenol and COD were 97.34%and 86.96%.When the catalyst was repeated for 6 times,the removal rate of phenol was still 86.57%,and the leaching performance of iron and nickel was lower than Integrated Wastewater Discharge Standard,which would not cause secondary pollution.?4?In the heterogeneous Fe-Ni/CSAC ozone-catalyzed oxidation system,it was found that the degradation of phenol was dominated by the oxidation of superoxide radicals?·O₂^-?,while hydroxyl radicals?·OH?played a mutual assistance role.?5?From the three-dimensional fluorescence spectrum,it was concluded that the characteristic fluorescence intensity of phenol was significantly reduced,and the center position of the phenol fluorescence peak appeared red-shifted,indicating that the Fe-Ni/CSAC binary catalyst treated actual phenol Wastewater had certain removal ability.