Study On The Preparation Of Structured Three-dimensional Electrode And Its Degradation Of P-aminophenol

Many dangerous and toxic organic amine could be detected in surface water,groundwater and even drinking water.P-aminophenol（PAP）is one of these organic pollutants.PAP could be detected in the effluent of conventional wastewater treatment plants owing to the fact that PAP is toxic to microorganisms and difficult to be biodegraded.If this kind of waste water was discharged directly into the environment,the residual PAP may cause great threat to human health with long-term low-dose exposure and adverse ecological damage to water bodies.Therefore,it is urgent to develop an effective approach to degrade PAP in wastewater from environmental and health perspectives.In this paper,PAP pollutant was used as the research object,and block honeycomb activated carbon（AC）was used as the carrier for preparation of the particle electrodes.Two kinds of particle electrodes were prepared and applied for three-dimensional electrochemical degradation of PAP.The main contents are as follows:（1）The Ti O₂-loaded three-dimensional electrodes（AC@Ti）were prepared by a sol-gel method with block honeycomb structured activated carbon（AC）as the carrier.PAP simulated wastewater degradation efficiency was used to evaluate the performance of AC@Ti.The experimental results show that when the volume ratio of n-butyl titanate to ethanol was 1:1,the immersion time was 30 min,the water bath was used for drying,and the firing temperature was 550°C,the performance of the prepared three-dimensional electrode material was the best.SEM,XDR and BET were used to characterize the crystal structure and surface morphology of AC@Ti particle electrodes.The characterization results show that Ti O₂ was successfully loaded on the surface of AC and existed in the form of anatase,proved that the AC@Ti three-dimensional particle electrode was successfully prepared.（2）The three-dimensional electrodes doped with Cu O,Ni O,Zn O,Sb2O3 and Mn O（AC@Ti-Cu-Ni-Zn-Sb-Mn）were prepared by a sol-gel method with AC as the carrier.PAP simulated wastewater degradation efficiency was used to evaluate the performance of the prepared three-dimensional electrode materials.The experimental results show that when the molar ratio was Ti∶Cu∶Ni∶Zn∶Sb∶Mn=20∶1∶1∶1∶1∶2,and the firing temperature was 550°C,the prepared three-dimensional electrode material has the best performance.The AC@Ti-Cu-Ni-Zn-Sb-Mn particle electrodes were further characterized by SEM,XDR,XPS and BET.From the SEM characterization results,it can be seen that there were lots of tubular structures on the surface of the AC@Ti-Cu-Ni-Zn-Sb-Mn three-dimensional electrode calcined at 550°C.XRD results show that metal doping did not change the crystal form of Ti O₂,and it still existed in the form of anatase.The XPS results show that Cu,Ni,Zn,Sb and Mn existed in the form of Cu O,Ni O,Zn O,Sb₂O₃ and Mn O,respectively.The BET results show that the specific surface area of AC@Ti-Cu-Ni-Zn-Sb-Mn three-dimensional particle electrode was greatly increased than AC and AC@Ti.All the characterization results show that the AC@Ti-Cu-Ni-Zn-Sb-Mn three-dimensional particle electrode was successfully prepared.（3）The single factor experiment was used to optimize the degradation conditions of PAP.The experimental results show that when the conductivity was 6 ms/cm,the p H was 7,the aeration intensity was2.0 L/min,and the initial concentration of PAP was less than or equal to150 mg/L,the removal efficiency of PAP was the best,as high as 99.87%.The kinetic analysis of the degradation process of PAP shows that the degradation of PAP conformed to the first-order kinetic model.ESR was used to identify the free radicals generated in the electrolysis process,the intermediate products of PAP degradation were analyzed based on LC-MS,and the possible degradation mechanism of PAP was proposed.First,PAP was oxidized to p-benzoquinone,under the attack of·OH,the benzene ring was gradually opened and converted into butenedioic acid,which was then degraded into acetaldehyde,and the final mineralized products were CO₂ and H₂O.