College of Environment and Ecology,Chongqing University
National Natural Science Foundation of China (No. 51878090)
为去除水中典型的难降解污染物卡马西平（CBZ），构建了真空紫外/氯高级氧化体系，考察了基于真空紫外或自由氯的不同氧化体系中CBZ去除效能的差异；探究了pH、自由氯投加量、水中重碳酸盐、腐殖酸对真空紫外/氯体系去除CBZ效果的影响及自由氯在该体系中的衰减情况；通过自由基淬灭试验，进一步探究了在真空紫外/氯体系中氧化CBZ的主要活性物质。结果表明，在pH=6，氯投加量为8mg/L，CBZ初始浓度为30 μM，真空紫外/氯体系中反应16分钟后CBZ去除率超过99.5%；在相同条件下，真空紫外/氯体系去除CBZ的速率常数是真空紫外体系、UV/氯体系的1.75、5.30倍，真空紫外和自由氯具有协同去除CBZ作用；在酸性条件下，CBZ的去除效果较好，最佳反应pH为6；自由氯投加量是影响CBZ降解速率的重要因素，最佳自由氯投加量为8 mg/L；而水中重碳酸盐和天然有机物对CBZ的去除均呈现抑制作用；真空紫外/氯体系降解CBZ的过程中，自由氯消耗主要为紫外光激发消耗而与CBZ及降解产物反应较为微弱，该体系存在HO·和Cl·的氧化作用及直接光解作用。
In order to remove the typical refractory pollutant carbamazepine (CBZ) in water, a vacuum ultraviolet/chlorine advanced oxidation system was constructed, and the difference of CBZ removal efficiency in different oxidation systems based on vacuum ultraviolet or free chlorine was investigated; The effects of pH, free chlorine dosage, bicarbonate in water, and humic acid on the removal of CBZ by vacuum ultraviolet/chlorine system and the attenuation of free chlorine in the system were explored. Through the free radical quenching test, the main active substances that oxidize CBZ in the vacuum ultraviolet/chlorine system are further explored. The results showed that at pH=6, the chlorine dosage was 8mg/L, the initial CBZ concentration was 30 μM, the CBZ removal rate exceeded 99.5% after 16 minutes of reaction in the vacuum ultraviolet/chlorine system; under the same conditions, the vacuum ultraviolet/chlorine The rate constant of the system to remove CBZ is 1.75 and 5.30 times that of vacuum ultraviolet system and UV/chlorine system. Vacuum ultraviolet and free chlorine have a synergistic effect on removing CBZ. Under acidic conditions, the removal effect of CBZ is better, and the optimal reaction pH is 6; the dosage of free chlorine is an important factor affecting the degradation rate of CBZ, and the best dosage of free chlorine is 8 mg/L ; while bicarbonate and natural organic matter in the water both have an inhibitory effect on the removal of CBZ; during the degradation of CBZ by the vacuum ultraviolet/chlorine system, the main free chlorine consumption is Ultraviolet light excites and consumes and reacts weakly with CBZ and degradation products, the system has oxidation of HO· and Cl· and direct photolysis.