紫外激活过硫酸盐技术去除水中金霉素

摘要

To solve the deficiency of organic micro⁃pollutants removal in traditional technologies, the degradation study of chlortetracycline ( CTC) in aqueous solution using UV activated persulfate technology ( UV/PS combined process) was carried out. The removal effectiveness of CTC with UV process, PS process and UV/PS process was compared. Then the effects of initial CTC concentration, persulfate dose, as well as pH on the degradation rate of CTC were discussed. The active free radical in the reaction system was identified, and the reaction rate between the radical and CTC was determined. The results showed that CTC degradation with these three processes followed pseudo⁃first⁃order kinetic, and CTC removal efficiency can be significantly improved through the combination of UV process with PS process. The CTC degradation rate increased considerably as the persulfate dose increased, but decreased as the initial CTC concentration increased. The observed oxidation kinetic constant was influenced by pH values, and reached its highest and lowest level at pH 3 and 7 respectively.The active radical in the UV/PS process was SO4-·, and the reaction rate between CTC and SO4-·was 8.8×108 L·mol-1·s-1.%为解决传统工艺难以有效去除水中有机微污染物的问题，采用紫外激活过硫酸盐技术（ UV／PS联用工艺）降解水中残留的金霉素（ chlortetracycline， CTC），对比UV／PS联用工艺与单独UV工艺、单独PS工艺对金霉素的去除效果，考察底物初始浓度、氧化剂投加量、pH对金霉素降解的影响，鉴定反应系统中的活性自由基并求出其反应速率．结果表明：单独UV工艺、单独PS工艺和UV／PS联用工艺对金霉素的降解均符合表观一级反应动力学模型，并且UV工艺与PS工艺联用可以大大提高金霉素的去除率；较低的底物初始浓度和较高的氧化剂投加量可以提高金霉素的降解速率；pH对表观速率常数有一定影响，kobs在pH为3和7处分别达到最大值和最小值；UV／PS系统中参与氧化金霉素的主要活性自由基为SO4－·，其与金霉素的反应速率为8．8×108 L·mol－1·s－1．