Fe2O3-Kao@g-CN activated peroxymonosulfate remediation of bensulfuron methyl-polluted water and soil: Detoxification, soil properties and crop growth

Abstract

Peroxymonosulfate-based advanced oxidation processes (PMS-AOPs) have been frequently applied in environment remediation for the rapid degradation of organics, while the high PMS usage could increase economic cost and ecological risks. Therefore, efficient activation methods are highly needed. In this study, low cost and environmentally safe bi-mineral hybrid carbon Fe2O3-Kao@g-CN was designed and fabricated to efficiently activate PMS for the remediation of water and soil polluted by bensulfuron methyl (BSM). Specifically, the Fe2O3-Kao@g-CN/PMS system could utterly remove BSM from water within 90 min and showed satisfactory tolerance to environment variation. The toxic BSM could be degraded into 15 kinds of intermediates with lower toxicity, benefiting from various reactive species of SO4•−, O2•−, •OH and 1O2. Furthermore, the removal efficiency of BSM in polluted wheat and maize soil reached about 79.2 %-86.8 % with low doses of PMS (3.07 mg·g−1) and catalyst (2 %). The degradation system did not adversely affect the soil pH and the soil redox potential (Eh), while promoted soil potassium availability and crop growth. The biomass and length of wheat and maize in remediated soil was significantly increased by 26.2 %-346.4 % compared with those planted in BSM-contaminated soil. This work emphasized the application of Fe2O3-Kao@g-CN/PMS system for BSM detoxification in water and soil and its ecological risks, offering a theoretical and practical foundation for decreasing environment risk and ensuring crop growth in the environment remediation.