Study On Preparation Of Ni-Ce/OMC Particle Electrode And Electrocatalytic Ozonation To Degrade High-salinity Organic Wastewater

High-salinity organic wastewater belongs to refractory wastewater because of its high salt content and many kinds of refractory organic pollutants,which has the effect of“carcinogenic,teratogenic and mutagenic”.Hybrid electrocatalytic ozonation（3D/O₃）process combines the action of electrocatalysis and ozonation to degrade high-salinity organic wastewater,which is a treatment technology with development prospect.However,the particle electrode used in 3D/O₃ process has many shortcomings,such as simple structure,poor catalytic effect on electrocatalysis and ozonation,poor stability and great influence on p H.In order to improve the degradation performance,it is very important to develop particle electrodes with high catalytic activity and for electrochemistry and ozone.In this paper,Ni_0.2-Ce_0.2/ordered mesoporous carbon（OMC）/granular active carbon（GAC）particle electrodes were developed and investigated the catalytic activity and degradation effects.Ni_0.2-Ce_0.2/OMC/GAC particle electrodes with a Ni:Ce weight ratio of 1:1 were synthesized to improve the degradation effect of 3D/O₃ process,and the morphology and performance of catalysts were studied.The addition of Ni-Ce promoted the dispersion of Ni and Ce and improved the catalytic performance.Ce is able to rapidly store and release oxygen through Ce³⁺/Ce⁴⁺conversions to form oxygen vacancy,which increases the oxidation capacity of the material.Ni_0.2-Ce_0.2/OMC catalyst has higher redox peak current,and k values were Ni_0.2-Ce_0.2/OMC（0.157）>Ni_0.2/OMC（0.017）>Ce_0.2/OMC（0.014）,indicating a higher redox activity for O₂ and O₃.The degradation effect of Ni_0.2-Ce_0.2/OMC/GAC particle electrode on simulated high-salinity wastewater was studied.Under the conditions of current of 10 m A,solid-liquid ratio of 5:150,p H value of 2,and initial concentrations of carbamazepine and norfloxacin of 25 mg/L and 20 mg/L,the removal rates of simulated high-salinity carbamazepine and norfloxacin wastewater by Ni_0.2-Ce_0.2/OMC/GAC were 99.7%and 100.0%,respectively.The generation mechanisms of·OH by 3D/O₃ process were analyzed.By comparing the degradation conditions and mechanisms of the two pollutants,found that the simulated high-salinity carbamazepine wastewater has a higher mineralization rate.The degradation effect of Ni_0.2-Ce_0.2/OMC/GAC particle electrode on the actual high-salinity organic wastewater was studied.Under the conditions of current 10 m A,solid-liquid 5:150 and ozone concentration 32.0 mg/L,the COD removal rate of Ni_0.2-Ce_0.2/OMC/GAC on the actual high-salinity organic wastewater was 93.7%.After the degradation,the species and concentration of organic compounds in the actual high-salinity organic wastewater decreased significantly and degraded into small molecule acids.The particle electrode has good stability.The prepared particle electrode can effectively reduce the influence of p H and provide theoretical and technical support for the practical application of 3D/O₃ process in degrading high-salt organic wastewater.