紫外联用高级氧化技术降解氯霉素试验研究

Degradation of Chloramphenicol by Ultraviolet Advanced Oxidation Technology

为了实现紫外高级氧化技术在实际水处理中去除抗生素的应用,以氯霉素(CAP)为研究对象,对比了静态试验中紫外技术,连续流下单独紫外技术、紫外高级氧化技术(UV/H2O2、UV/PS)对氯霉素的去除效能。进一步分析了连续流下紫外光强、紫外光波长、停留时间、氧化剂投加量、氯霉素初始浓度和原水水质等因素对去除效果的影响。研究发现静态流单独紫外对于氯霉素120 min照射后,降解率大于80%,降解速率符合一阶动力学。实际连续流应用情况受停留时间限制,单独紫外氧化技术对氯霉素去除率较低。相同停留时间下,基于紫外UV/H2O2和UV/PS高级氧化技术对氯霉素的去除率大幅提高,分别达到58%和43%,紫外光激活氧化剂产生强氧化自由基(OH·,SO42-·),起到主要作用。同时增大紫外光强、氧化剂投加量及降低氯霉素的初始浓度会增加氯霉素的降解效能。研究发现原水中存在的无机和有机污染物会降低紫外高级氧化技术对氯霉素的去除效率,但能同步去除原水中常规污染物,为基于紫外高级氧化技术的实际水处理推广应用提供了可能。

To realize the application of ultraviolet advanced oxidation technology on removing antibiotics in actual water treatment,this study took chloramphenicol(CAP)as the research object,and compared its removal efficiency by ultraviolet technology,ultraviolet advanced oxidation technology(UV/H2 O2,UV/PS)under static and continuous flow respectively. The influence of factors such as ultraviolet light intensity, ultraviolet light wavelength, residence time, oxidant dosage, initial concentration of chloramphenicol and raw water quality on the removal effect was further analyzed. The study results show that the ultraviolet technology under static flow can degrade more than 80% chloramphenicol after an irradiation of 120 min,and the degradation conforms to the first-order kinetics. Chloramphenicol removal rate by ultraviolet technology under continuous flow is limited due to the short irradiation time,but UV/H2 O2 and UV/PS processes can enhance the removal rate of chloramphenicol to 58% and 43%,owing to the oxidation effect of oxidizing free radicals activated by ultraviolet.Increasing the intensity of ultraviolet light,the dosage of oxidant and reducing the initial concentration of chloramphenicol will increase the degradation of chloramphenicol. The presence of inorganic and organic pollutants in raw water will reduce the removal efficiency of UV advanced oxidation technology for chloramphenicol,but the inorganic and organic pollutants can also be removed during the oxidation,which provides the possibility for the promotion and application of UV advanced oxidation technology on the actual water treatment.