Guan Ying-Hong, Chen Jin, Chen Li-Jun, Jiang Xin-Xin, Fu Qiang
School of Water Conservancy and Civil Engineering, Northeast Agricultural University, Harbin, China.
Front Chem. 2020 Sep 25;8:581198. doi: 10.3389/fchem.2020.581198. eCollection 2020.
In this study, we compared the decontamination kinetics of various target compounds and the oxidation by-products (bromate and chlorate) of PMS, PDS, and HO under UV irradiation (UV/PMS, UV/PDS, UV/HO). Probes of different reactivity with hydroxyl and sulfate radicals, such as benzoic acid (BA), nitrobenzene (NB), and trichloromethane (TCM), were selected to compare the decontamination efficiency of the three oxidation systems. Experiments were performed under acidic, neutral, and alkaline pH conditions to obtain a full-scale comparison of UV/peroxides. Furthermore, the decontamination efficiency was also compared in the presence of common radical scavengers in water bodies [bicarbonate, carbonate, and natural organic matter (NOM)]. Finally, the formation of oxidation by-products, bromate, and chlorate, was also monitored in comparison in pure water and tap water. Results showed that UV/HO showed higher decontamination efficiency than UV/PDS and UV/PMS for BA degradation while UV/HO and UV/PMS showed better decontamination performance than UV/PDS for NB degradation under acidic and neutral conditions. UV/PMS was the most efficient among the three processes for BA and NB degradation under alkaline conditions, while UV/PDS was the most efficient for TCM degradation under all pH conditions. In pure water, both bromate and chlorate were formed in UV/PDS, small amounts of bromate and rare chlorate were observed in UV/PMS, and no detectable bromate and chlorate were formed in UV/HO In tap water, no bromate and chlorate were detectable for all three systems.
在本研究中，我们比较了各种目标化合物的去污动力学以及过一硫酸氢钾（PMS）、过二硫酸钾（PDS）和过氧化氢（HO）在紫外线照射下（UV/PMS、UV/PDS、UV/HO）的氧化副产物（溴酸盐和氯酸盐）。选择了与羟基和硫酸根自由基反应性不同的探针，如苯甲酸（BA）、硝基苯（NB）和三氯甲烷（TCM），以比较这三种氧化体系的去污效率。实验在酸性、中性和碱性pH条件下进行，以全面比较紫外线/过氧化物体系。此外，还比较了在水体中存在常见自由基清除剂[碳酸氢盐、碳酸盐和天然有机物（NOM）]时的去污效率。最后，还比较监测了在纯水和自来水中氧化副产物溴酸盐和氯酸盐的形成情况。结果表明，在降解BA方面，UV/HO比UV/PDS和UV/PMS具有更高的去污效率；而在酸性和中性条件下，对于降解NB，UV/HO和UV/PMS比UV/PDS表现出更好的去污性能。在碱性条件下，UV/PMS是三种工艺中降解BA和NB最有效的；而在所有pH条件下，UV/PDS是降解TCM最有效的。在纯水中，UV/PDS中形成了溴酸盐和氯酸盐，UV/PMS中观察到少量溴酸盐和极少量氯酸盐，UV/HO中未形成可检测到的溴酸盐和氯酸盐。在自来水中，所有三种体系均未检测到溴酸盐和氯酸盐。
