Study On Efficient Microwave Catalytic Oxidation Degradation Of Aureomycin Wastewater And The Performance Of Microwave Catalyst

People’s livelihood is the top priority and sewage treatment is the key.In recent years,new water pollution sources such as pharmaceuticals and personal care products（PPCPs）,endocrine disruptors and other serious threats to human health and ecological balance.Because conventional sewage treatment plants were not designed with new pollution treatment in mind at the beginning,it is very difficult and costly to remove antibiotics from wastewater,so it is urgent to develop an efficient,energy-saving,green,clean and easily regulated method for the degradation of new pollution.Microwave has been introduced into sewage treatment because of its uniform body heating method and unique electromagnetic field effect.Which compared with traditional methods has the advantages of high efficiency,rapid,clean and sustainable,strong operability and wide applicability.However,microwave induction,microwave enhancement,microwave coordination and other mainstream technologies are highly dependent on oxidants,which bring great security risks and economic burden to industrial production.Therefore,a microwave catalytic high efficiency oxidative degradation（MCOD）method for aureomycin（CTC）antibiotic wastewater without additional oxidant was proposed in this study.In this paper,a metal oxideα-MnO₂ nanowires and MnO₂-Co O/AC（MCA）and Zn Fe₂O₄-Fe₂O₃/AC（ZFIO-AC）activated carbon fund composite nanomaterials were prepared for microwave catalytic oxidation degradation of chloromycin containing wastewater,realizing the efficient degradation and mineralization of CTC.It is confirmed that both metal oxide and spinel oxide modified metal oxide nanomaterials can enhance the degradation of antibiotics.The effects of different reaction conditions on the degradation rate of CTC(DR_CTC)under microwave irradiation were investigated and the reaction parameters were optimized.The specific contents and results are as follows:（1）Nano-lineα-MnO₂ was prepared by hydrothermal method.The degradation rate of100 m L CTC（100 mg/L）was 82.07%and the mineralization rate wass 62.48%when the microwave power was 700 W,the catalyst dosage was 1.5 g/L,CTC simulated wastewater p H was 7 and the irradiation time was 10 min.Under the same conditions,the degradation rate reached 89.47%when the time was extended to 20 min.After three cycles,the metal dissolution rate of manganese inα-MnO₂ was 0.96 mg/L.（2）10%-MCA was prepared by coprecipitation-impregnation method.For the above CTC simulated wastewater,under the irradiation of 500W microwave for 7 min and adding0.3 g catalyst,the DR_CTC reached 98.49%and the mineralization rate was 89.74%.The influence of heavy metal Cr⁶⁺on the degradation process of CTC was explored.The CTC solution containing 150 mg/L Cr⁶⁺was irradiated at 700 W,the CTC-Cr⁶⁺complex was formed and the content of Cr decreased from 4.64 mg/L to 1.92 mg after 10min.（3）10%-ZFIO/AC magnetic metal oxidation complex was prepared by precipitation and impregnation method.When the microwave power was 700 W,irradiation time was 7min,CTC concentration was 100 mg/L,p H was 7,and 0.3 g catalyst was added,DR_CTCreached 95.3%and mineralization rate reached 81.76%.After five cycles,the degradation rate of CTC by 10%-ZFIO/AC remained at 90.1%,showing good stability.（4）Through free radical scavenging experiments and fluorescence probe technology,it was confirmed that the degradation principle of MCOD is that the pollutants contact with·OH,·O₂^-and other strong oxidizing groups excited by microwave irradiation repeatedly,and eventually mineralized into harmless inorganic small molecules such as CO₂ and H₂O.And based on microwave catalyst ZFIO/AC,the reaction kinetics of CTC degradation process of MCOD was calculated.It was confirmed that the reaction is a pseudo first order kinetics process,and the reaction rate constant increased nearly 1.9 times with the increase of microwave power from 100 W to 700 W.Therefore,the simple regulation of pollutant degradation process could be achieved by adjusting the microwave power.