Degradation Of Chloramphenicol Under UV/H₂O₂ Technology And Its Influence On Chlorine Disinfection Process

Chloramphenicol has strong effects and wide distribution in terms of medical treatment as a broad-spectrum antibacterial.What's more,it is price moderate and can be used as animal growth promoters.During the process of generation and use,some of the remaining chloramphenicol will be discharged into the water.The accumulation of chloramphenicol can cause some disease even though it is little in the drinking water system.UV/H2O2 is a kind of advanced oxidation technology with low selectivity and high degradation efficiency.Under UV/H2O2 process,chloramphenicol can be completely degraded.The main purpose of this article is to explore the degradation kinetics of chloramphenicol under the UV/H2O2 process,and to explore the competitive effect of natural organics during the degradation process.In addition,chlorination has been performed after the degradation process to explore the disinfection by-products,so as to evaluate the safety of UV/H2O2 technology in the water treatment process.The main contents and conclusions are as follows:(1)Chloramphenicol can be degraded to small molecule organic matters completely under UV/H2O2 process.Experimental results show that H2O2 has no effect on chloramphenicol degradation.The dagradation rate of chloramphenicol is 3.75×10-3 s-1,under UV/H2O2 process,which 1.6 times UV alone process.The degradation rate coefficient of chloramphenicol was influenced by many factors,such as UV dose,initial concentration of H2O2 and chloramphenicol.The genetic toxicity of chloramphenicol reduced from 7.01 ?g L-1 to 0.2 ?g L-1 under UV/H2O2 process.(2)Humic acid can be degraded under UV/H2O2 process and has a competitive effect on the degradation of chloramphenicol.Effects of humic acids are not only related to the initial concentration of humic acid,but also related to the relative amount of humic acid and chloramphenicol.During the application process,the influence of two factors should be considered comprehensively.(3)Chloramphenicol and its degradation products during UV/H2O2 process all can be used as the precursor for disinfecting by-products.The experimental results shown that chloramphenicol can increase the generation of haloacetic acid,its formation can be effectively controlled after UV/H2O2 process.The increase of initial chlorine concentration can decrease the generation of the byproducts of bromine disinfection when the water contains bromide ions.The above research has important theoretical significance and application value for the treatment of chloramphenicol in water.