School of Environmental and Chemical Engineering, Shanghai Applied Radiation Institute, Shanghai University, Shanghai 200444, China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, China; State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
Pudong New Area Environmental Monitoring Station, No. 51 Lingshan Road, Pudong New Area, Shanghai, China.
Sci Total Environ. 2020 Feb 10;703:135013. doi: 10.1016/j.scitotenv.2019.135013. Epub 2019 Nov 3.
Electron beam (EB) has proven to be an effective advanced oxidation reduction process (AORP) to degrade the psychiatric drug carbamazepine (CBZ); however, the degradation mechanism and the toxicity of the final reaction solutions to aquatic microorganisms needed further investigation. In this study, CBZ was eventually degraded and even mineralized by EB treatment, where the degradation of CBZ followed the pseudo-first-order kinetics with R > 0.98. Acidic conditions, presence of an additional oxidant (2.5 mmol L HO), and O/air-saturated conditions improved the degradation efficiency of CBZ, as well as the radiation chemical yield (G-value defined as the efficiency of the irradiation process). Concentrations of transient reactive species (TRS) caused by EB were quantified under different conditions at doses of 0.956 and 3.17 kGy, and the apparent quantum yield of CBZ degradation was in the order of OH > H > e. However, the contribution of these species to CBZ degradation was in the order of OH > e >H due to the generation of only a small amount of H. Findings regarding the changes of in CBZ degradation intermediates, short-chain fatty acids (SCFAs), and total organic carbon showed that CBZ can gradually be mineralized into CO/CO, HO, and NH/NH by the EB process. Additionally, an excellent rotifer survival rate after 5-day culturing in the reaction solutions resulting from 5-kGy treatment indicated that EB can be a safe AORP to mineralize CBZ in solution. These findings provide scientific proof for the EB being an effective AORP for removal of psychiatric drugs from aqueous solutions, laying the foundation for future remediation research.
电子束 (EB) 已被证明是一种有效的高级氧化还原过程 (AORP)，可降解精神药物卡马西平 (CBZ)；然而，降解机制和最终反应溶液对水生微生物的毒性仍需进一步研究。在本研究中，CBZ 最终被 EB 处理降解甚至矿化，CBZ 的降解遵循准一级动力学，R > 0.98。在酸性条件下，存在额外的氧化剂 (2.5 mmol L HO) 和充氧/空气饱和条件下，可提高 CBZ 的降解效率，以及辐射化学产率 (G 值定义为辐照过程的效率)。在剂量为 0.956 和 3.17 kGy 下，在不同条件下定量了 EB 产生的瞬态活性物质 (TRS) 浓度，CBZ 降解的表观量子产率顺序为 OH > H > e。然而，由于仅生成少量 H，这些物质对 CBZ 降解的贡献顺序为 OH > e > H。关于 CBZ 降解中间体、短链脂肪酸 (SCFAs) 和总有机碳变化的研究结果表明，CBZ 可通过 EB 过程逐渐矿化为 CO/CO、HO 和 NH/NH。此外，在 5-kGy 处理后的反应溶液中进行 5 天培养后轮虫的存活率很高，表明 EB 可以作为一种安全的 AORP 将 CBZ 矿化到溶液中。这些发现为 EB 作为一种有效的从水溶液中去除精神药物的 AORP 提供了科学依据，为未来的修复研究奠定了基础。
