Ozone Catalytic Oxidation Method For Advanced Treatment Of Antibiotic Wastewater

The composition of pharmaceutical wastewater was complex,with many kinds of organic compounds,high COD and BOD5,high concentration of NH3-N and solid suspend SS,deep chroma,and high volatility.At present,domestic and foreign pharmaceutical companies used the traditional pre-treatment and secondary biochemical treatment processes to treat their wastewater,but secondary biochemical wastewater still contained some organic matter that more difficult to degrade,it was difficult to achieve the new standard of China's pharmaceutical wastewater pollutant emissions.Therefore,deep treatment of wastewater was required.In this paper,impregnation method was used to prepare high efficient and cheap catalysts,and used in heterogeneous catalytic ozonation system for the treatment of refractory organic wastewater.With biochemical effluent of antibiotics as research object,it were investigated that the effects of various process conditions on the removal of organic compounds in antibiotic wastewater,the mechanism of ozone oxidation treatment of antibiotic wastewater was also studied.The catalyst was prepared by impregnation method.The catalytic activity of the?-Al2O3 supported copper oxide and iron oxide was high,which was prepared under the following conditions that impregnation solution 1.25mol(Cu²⁺)/L,C(Fe³⁺):C(Cu²⁺)=1?1,calcination temperature 500?,calcination time 5h.The COD removal rate was stable after repeated seven cycles of the catalyst,and leaching of iron and ions was less,which indicated that the stability of the catalyst was good.The CuO-Fe2O3/?-Al2O3 catalyst prepared under the optimal conditions was characterized by SEM,XRD,XRF,BET.The active components supported by the catalyst were proved to be CuO,Fe2O3,with the CuO content of 9.676%,Fe2O3 content of 10.84%.The effect was the most obvious on the degradation of normal secondary biochemical effluent by CuO-Fe₂O₃/?-Al₂O₃/H₂O₂/O₃,The results show that COD removal rate was62.96%when catalyst dosage 2g/L,pH=9,H₂O₂ dosage 3.6mg/L,ozone flow rate1.0L/min.It was deduced that the enhancement of catalytic activity was responsible for generating more radicals by radical scavenger detection.Theabnormalsecondarybiochemicaleffluentwastreatedby CuO-Fe₂O₃/?-Al₂O₃/H₂O₂/O₃,The results show that COD removal rate was 88.74%when catalyst dosage 1g/L,pH=9,H₂O₂ dosage 4mg/L,ozone flow rate 1.0L/min.The treated wastewater COD dropped to 96.54mg/L,it could achieved a new standard of China's pharmaceuticalwastewaterpollutantemissions.Comparedwiththe CuO-Fe2O3/?-Al2O3/O3 coupling biologically active fouling process,the process requires no subsequent processing,and had many advantages such as short operation cycle,low energy consumption,high processing capacity,simple process and small equipment footprint.The operation Simple,low cost.