Remediation of atrazine contaminated soil by microwave activated persulfate system: Performance, mechanism and DFT calculation
Remediation of atrazine contaminated soil by microwave activated persulfate system: Performance, mechanism and DFT calculation
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DOI：
10.1016/j.jclepro.2023.136546
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发表时间：
2023-02
影响因子：
11.1
通讯作者：
Jianhua Qu;R. Liu;Xuewei Bi;Zhuoran Li;Kaige Li;Qizhao Hu;Xinru Zhang;Guangshan Zhang;
中科院分区：
文献类型：
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作者：
Jianhua Qu;R. Liu;Xuewei Bi;Zhuoran Li;Kaige Li;Qizhao Hu;Xinru Zhang;Guangshan Zhang;
由于高浓度的污染物和完全的栖息地破坏，农药污染场地的有效补救具有挑战性。本文以阿特拉津（ATZ）为代表，提出了微波（MW）活化过硫酸盐（PS）修复有机氯农药污染土壤的方法。结果表明，MW/PS系统处理60 min后对ATZ （50 mg/kg）的降解率达到97.9%，优于常规热活化PS系统，且在适宜的PS浓度（24 mmol/L）、MW功率（400 W）和水土比（1:1）、较高的微波温度（80℃）条件下具有较好的降解效果。此外，MW/PS系统对共存物质cl−、hc_3−和h2p_4−具有较高的耐受性，适宜的有机质含量有利于ATZ在土壤中的降解。由S O 4•−、O H•、O 2•−和1 O 2组成的活性氧有助于ATZ的分解，其中o2∙−起主要作用。结合HPLC/MS谱和DFT计算阐明了ATZ的降解途径，在毒性评价方面，MW/PS体系有效减轻了ATZ的总体毒性。此外，MW/PS系统对三氯乙烯、四氯、六氯苯和氯丹等有机氯农药具有良好的降解效果，表明该系统在有机氯农药污染场地的修复中具有很大的潜力。
Effective remediation of pesticide-contaminated sites is challenging due to high concentrations of pollutants with complete habitat destruction. Herein, microwave (MW)-activated persulfate (PS) system was proposed for remediation of organochlorine pesticide contaminated soil with atrazine (ATZ) as representation. The results revealed that the MW/PS system could achieve 97.9% of ATZ (50 mg/kg) degradation after treatment of 60 min, superior to that by conventional heat-activated PS. And more excellent degradation performance was identified in relatively higher microwave temperature (80° C) with appropriate PS concentration (24 mmol/L), MW power (400 W) and water-soil ratio (1: 1). Moreover, the MW/PS system possessed high tolerance to co-existing substances including C l−, H C O 3− and H 2 P O 4−, and appropriate organic substance content favored ATZ degradation in soil. Reactive oxygen species consisting of S O 4•−, O H•, O 2•− and 1 O 2 contributed to ATZ decomposition, among which O 2∙− played a principal role. The ATZ degradation pathway was then elucidated by combination of HPLC/MS spectra and DFT calculations, and ATZ overall toxicity was effectively alleviated in MW/PS system in term of toxicity assessment. Additionally, the MW/PS system presented high-performance degradation on such organochlorine pesticides as trichloro ethylene, tetrachloride, hexachlorobenzene and chlordane, suggesting great potentials of this system for remediation of organochlorine pesticides contaminated sites.