Study On Electrochemical Catalytic Oxidation Of Phenol Containing Wastewater By Polyaniline Enhanced TiO₂/ACF-Graphite Electrode

Phenolic wastewater is a common refractory organic.Due to its intense toxicity to organisms and degrading difficulties,the water pollution caused by phenolic attracts great attention,and many researchers have focused on the treatment of phenolic wastewater.Electrochemical treatments of phenolic wastewater have been applied widely due to the features of high efficiency,clean and environment-friendly,none or less chemical reagents are consumed and easy to automate.The electrode material used in these electrochemical treatments is one of the key factors that affect the electrochemical oxidation.Recently,numerous studies have focuses on the development of new electrodes with high oxygen evolution potential and high performance catalytic.For example,boron doped diamond electrodes and porous carbon matrix catalytic electrodes.Unfortunately,the preparation of this electrode is complicated and expensive,which limits its application in the field of wastewater treatment.Therefore,it is urgent to study the electrode materials and processing technology,which are excellent in electro-catalysis,high in current efficiency and easy to be produced in large scale.In this paper,the traditional conductive graphite electrode as the base material,and the activated carbon fiber(ACF)combined with activated carbon fiber felt with high specific surface area and adsorption characteristics,using titanium dioxide ship-in-a-bottle method respectively with catalytic activity(Ti O2)and polyaniline(PANI)firmly modified in ACF,prepared with catalytic performance,electro-catalytic anode also has good adsorption properties.Further,XPS,SEM,semiconductor tester,electrochemical workstation and other means were used for the preparation of electrode materials of surface morphology,surface chemical properties and electrode performance characterization;at the same time with the production of hydroxyl radicals(·OH)on the catalytic degradation of phenol,and the current efficiency and determination of recycling efficiency.Evaluation of the catalytic performance and the stability of the electrode preparation were discussed.In addition,the important factors affecting the performance of the electrode and the mechanism of electro-catalytic degradation of phenol by the preparation electrode were also discussed.The experimental results show that:(1)Conductive PANI can significantly improve the conductivity of ACF.The more PANI modification,the better the conductivity of ACF.(2)The modification order of PANI and Ti O2 also has a certain effect on the rate of ·OH production and the degradation rate of phenol.The first modification of PANI,the ACF electrode of Ti O2 and the degradation rate of phenol to the phenol degradation rate are better than the ACF electrodes that first modified Ti O2 and then modified PANI.(3)The electro-catalytic activity of ACF anode modified by PANI and Ti O2 is influenced by the comprehensive effect of PANI conductivity,Ti O2 electro-catalytic activity and ACF adsorption properties.PANI and Ti O2 have synergistic catalytic oxidation,but the modification of the two groups will affect the adsorption properties of ACF to a certain extent.For fast and thorough degradation of low concentration phenol,the comprehensive performance of modified ACF electrode shows that M14 Ti O2/0.01PANI/ACF electrode material is the best.(5)the electro-catalytic stability of the PANI and Ti O2 double component modified ACF anode prepared by the "bottled shipbuilding method" has been greatly improved,and the practical performance of the modified electrode has been greatly improved.