陕西师范大学地理科学与旅游学院环境科学系, 西安 710119
Department of Environmental Science, School of Geography and Tourism, Shaanxi Normal University, Xi′an 710119, China
)和出水有机物(effluent organic matter, EfOM)对PRM降解效果的影响,并研究了PRM在类Fenton体系中的削减情况;同时,根据溶液总有机碳(TOC)的矿化、芳香性中间产物和小分子有机酸的生成,阐明了在紫外/氯体系中PRM的降解机理。结果表明,当PRM初始浓度为5 μmol·L
。2种EfOM的引入对PRM降解产生抑制作用,且憎水性EfOM的抑制作用更加显著。TOC矿化实验和降解路径分析结果表明,紫外/氯体系对PRM有一定的矿化作用且PRM首先通过连续的羟基化作用转化为苯甲酸等物质,同时母体化合物和中间体还可继续被氧化为小分子有机酸。PRM中的氮元素最终以
。
Primidone (PRM) was selected as target contaminant in this study, and the degradation efficiency and reaction mechanism of PRM in UV/chlorine advanced oxidation process were investigated. The effects of solution pH, common anions (Cl
) and effluent organic matter (EfOM) on the degradation of PRM were studied, respectively. PRM decay in Fenton-like system was also studied. Meanwhile, the degradation mechanism of PRM in UV/chlorine system was identified based on TOC mineralization, the formation of aromatic intermediate products and small molecular acid. The results showed that when the initial concentrations of PRM and free chlorine were 5 μmol·L
, respectively, and solution pH was 7, PRM removal rate was 84% in 10 min. ClO· played a leading role in PRM degradation, followed by ·OH, while Cl
· did not participate in the conversion process. When solution pH was 6.2, the best degradation effect of pollutant occurred. The PRM degradation was almost unaffected by Cl
. When the Fe
. The introduction of two kinds of EfOM could inhibit the PRM degradation, and the hydrophobic EfOM played a more significant role. TOC mineralization experiment and degradation path analysis showed that UV/chlorine AOP had a certain mineralization effect on PRM, which first converted to benzoic acid and other substances through continuous hydroxylation, and the precursor and intermediates could continue to be oxidized into small molecular organic acids. It was found that the nitrogen elements in PRM molecular eventually existed in the form of
under the attack of various active radicals.
.
Degradation of PRM and NB in the UV/chlorine process
TBA和IPA在pH=6.2和pH=8.2条件下对紫外/氯体系降解PRM的影响
Effect of TBA and IPA on the degradation of PRM at pH 6.2 and 8.2
Effect of pH on the degradation of PRM
and EfOM on the degradation of PRM.
对紫外/氯体系降解PRM的影响及自由基贡献
on PRM degradation by the UV/chlorine and the corresponding contribution of radicals
PRM在紫外/氯体系中的降解、矿化和FC的消耗
PRM degradation, variation of TOC, and consumption of free chlorine in the UV/chlorine process
PRM在紫外/氯体系降解过程中小分子有机酸的浓度变化
Variation in the concentrations of low molecular weight organic acids during PRM degradation in the UV/chlorine process
during PRM degradation in the UV/chlorine process
Proposed pathways of PRM degradation by the UV/chlorine process
[1] | 秀措, 王尘辰, 吕永. 潮汕地区入海河流及水生生物中PPCPs分布特征及风险评估[J]. 环境科学, 2020, 41(10): 4514-4524. |
[2] | 高泽晨, 张天阳, 黄飘怡. 应用紫外/氯组合工艺去除微污染原水中氨氮的特性研究[J]. 环境科学学报, 2019, 39(10): 3427-3433. |
[3] | BEITZ T, BECHMANN W, MITZNER R. Investigations of reactions of selected azaarenes with radicals in water chlorine and bromine radicals[J]. Journal of Physical Chemistry A, 1998, 102(34): 6766-6771. doi: 10.1021/jp980655a |
[4] | FANG J Y, FU Y, SHANG C. The roles of reactive species in micropollutant degradation in the UV/free chlorine system[J]. Environmental Science & Technology, 2014, 48(3): 1859-1868. |
[5] | ZHANG X, HE J, XIAO S, et al. Elimination kinetics and detoxification mechanisms of microcystin-LR during UV/chlorine process[J]. Chemosphere, 2019, 214: 702-709. doi: 10.1016/j.chemosphere.2018.09.162 |
[6] | SUN P, LEE W N, ZHANG R, et al. Degradation of deet and caffeine under UV/chlorine and simulated sunlight/chlorine conditions[J]. Environmental Science & Technology, 2016, 50(24): 13265-13273. |
[7] | 骆靖宇, 李学艳, 李青松. 紫外活化过硫酸钠去除水体中的三氯卡班[J]. 中国环境科学, 2017, 37(9): 3324-3331. doi: 10.3969/j.issn.1000-6923.2017.09.015 |
[8] | DREWES J E, CROUE J P. New approaches for structural characterization of organic matter in drinking water and wastewater effluents[J]. Water Supply, 2002, 2(2): 1-10. doi: 10.2166/ws.2002.0039 |
[9] | BOLTON J R, STEFAN M I, SHAW P S, et al. Determination of the quantum yields of the potassium ferrioxalate and potassium iodide-iodate actinometers and a method for the calibration of radiometer detectors[J]. Journal of Photochemistry and Photobiology A:Chemistry, 2011, 222(1): 166-169. doi: 10.1016/j.jphotochem.2011.05.017 |
[10] | CHENG S, ZHANG X, YANG X, et al. The multiple role of bromide ion in ppcps degradation under UV/chlorine treatment[J]. Environmental Science & Technology, 2018, 52(4): 1806-1816. |
[11] | BUXTON G V, GREENSTOCK C L, HELMAN W P. Critical review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals (?OH/?O?) in squeous solution[J]. Journal of Physical and Chemical Reference Data, 1988, 17(2): 513-886. doi: 10.1063/1.555805 |
[12] | MERTENS R, VONSONNTAG C. Photolysis(λ=254 nm) of tetrachloroethene in aqueous solution[J]. Photochemistry Photobiol Science, 1995, 85(1/2): 1-9. |
[13] | TETON S. MELLOUKI A, LEBRAS G, et al. Rate constants for reactions of oh radicals with a seires asymmetrical ethers and tert-butyl alcohol[J]. International Chemistry, 1996, 28(4): 291-297. |
[14] | PARKER K M, MITCH W A. Halogen radicals contribute to photooxidation in coastal and estuarine waters[J]. Parkar and Mitch, 2016, 113(21): 5868-5873. |
[15] | WATTS M J, LINDEN K G. Chlorine photolysis and subsequent oh radical production during UV treatment of chlorinated water[J]. Water Research, 2007, 41(13): 2871-2878. doi: 10.1016/j.watres.2007.03.032 |
[16] | 高睿, 杨潇, 冯天宇. 紫外/氯工艺中磺胺类药物的转化机理和毒性评价[J]. 环境化学, 2021, 40(5): 1319-1329. |
[17] | DAUGHTON C G, TERNES T A. Pharmaceuticals and personal care products in the environment: Agents of subtle change?[J]. Enviromental Health Perspectives, 1999, 107(6): 907-938. |
[18] | LIU X, LIANG C, LIU X. Occurrence and human health risk assessment of pharmaceuticals and personal care products in real agricultural systems with long-term reclaimed wastewater irrigation in Beijing, China[J]. Ecotoxicology and Environmental Safety, 2020, 190(1): 1-11. |
[19] | KONG X, JIANG J, MA J, et al. Degradation of atrazine by UV/chlorine: Efficiency, influencing factors, and products[J]. Water Research, 2016, 90(1): 15-23. |
[20] | ZHU Y, WU M, GAO N, et al. Degradation of phenacetin by the UV/chlorine advanced oxidation process: Kinetics, pathways, and toxicity evaluation[J]. Chemical Engineering Journal, 2018, 335(1): 520-529. |
[21] | 罗从伟, 军 马, 进 江. UV/H2O2降解2, 4, 6/三氯苯甲醚动力学及产物研究[J]. 中国环境科学, 2017, 37(5): 1831-1837. doi: 10.3969/j.issn.1000-6923.2017.05.028 |
[22] | WANG Y, COUET M, GUTIERREZ L, et al. Impact of dom source and character on the degradation of primidone by UV/chlorine: Reaction kinetics and disinfection by-product formation[J]. Water Research, 2020, 172: 115463. doi: 10.1016/j.watres.2019.115463 |
[23] | BU L, ZHU N, LI C, et al. Susceptibility of atrazine photo-degradation in the presence of nitrate: Impact of wavelengths and significant role of reactive nitrogen species[J]. Journal of Hazardous Materials, 2020, 388: 121760. |
[24] | RICHARD G. ZEPP J H, HEINZ B. Nitrate-induced photooxidation of trace organic chemicals in water[J]. Environmental Science & Technology, 1987, 21: 443-450. |
[25] | WU Y T, BU L, DUAN X, et al. Mini review on the roles of nitrate/nitrite in advanced oxidation processes: Radicals transformation and products formation[J]. Journal of Cleaner Production, 2020, 273: 123065. doi: 10.1016/j.jclepro.2020.123065 |
[26] | XU L, SUN Y, GAN L, et al. Utilization of photochemical circulation between NO3? and NO2? in water to degrade photoinert dimethyl phthalate: Influence of organic media and mechanism study[J]. Applied Catalysis B:Environmental, 2019, 259: 117958. doi: 10.1016/j.apcatb.2019.117958 |
[27] | NETA P, HUIE R E, ROSS A B. Rate constants for reactions of inorganic radicals in aqueous solution[J]. Journal of Physical and Chemical Reference Data, 1988, 17(3): 1027-1284. doi: 10.1063/1.555808 |
[28] | LI A, ZHANG Z, LI P, et al. Nitrogen dioxide radicals mediated mineralization of perfluorooctanoic acid in aqueous nitrate solution with UV irradiation[J]. Chemosphere, 2017, 188: 367-374. doi: 10.1016/j.chemosphere.2017.08.170 |
[29] | HUANG Y, KONG M, WESTERMAN D, et al. Effects of HCO3- on degradation of toxic contaminants of emerging concern by UV/NO3-[J]. Environmental Science & Technology, 2018, 52(21): 12697-12707. |
[30] | 王雪凝, 张炳亮, 潘丙才. 市政污水二级出水中溶解性有机质在紫外/氯处理过程中的转化特性[J]. 环境科学, 2021, 42(8): 1-18. |
[31] | 赵刘柱, 敏吴, 朱延平. 紫外/氯降解非那西丁影响因素及机理研究[J]. 水处理技术, 2019, 45(3): 69-73. |
[32] | SUN B, WANG Y, XIANG Y, et al. Influence of pre-ozonation of dom on micropollutant abatement by UV-based advanced oxidation processes[J]. Journal of Hazardous Materials, 2020, 391: 122201. doi: 10.1016/j.jhazmat.2020.122201 |
[33] | YUAN Y, FENG L, XIE N, et al. Rapid photochemical decomposition of perfluorooctanoic acid mediated by a comprehensive effect of nitrogen dioxide radicals and Fe3+/Fe2+ redox cycle[J]. Journal of Hazardous Materials, 2020, 388: 121730. |
[34] | DING X, GUTIERREZ L, CROUE J P, et al. Hydroxyl and sulfate radical-based oxidation of RhB dye in UV/H2O2 and UV/persulfate systems: Kinetics, mechanisms, and comparison[J]. Chemosphere, 2020, 253: 126655. doi: 10.1016/j.chemosphere.2020.126655 |
[35] | ZHENG M, DANIELS K D, PARK M, et al. Attenuation of pharmaceutically active compounds in aqueous solution by UV/CaO2 process: Influencing factors, degradation mechanism and pathways[J]. Water Research, 2019, 164(1): 1-11. |
[36] | FIGUEREDO M A, RODRIGUEZ E M, CHECA M, et al. Ozone-based advanced oxidation processes for primidone removal in water using simulated solar radiation and TiO2 or WO3 as photocatalyst[J]. Molecules, 2019, 24(9): 1728-1745. doi: 10.3390/molecules24091728 |
[37] | LIU Y, YAN S, LIAN L, et al. Assessing the contribution of hydroxylation species in the photochemical transformation of primidone (pharmaceutical)[J]. Science of the Total Environment, 2019, 696: 133826. doi: 10.1016/j.scitotenv.2019.133826 |