Collaborative Innovation Center Atmospheric Environment and Equipment Technology, Nanjing, 210044, China.
School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, Nanjing, 210044, China.
Environ Sci Pollut Res Int. 2017 Oct;24(30):23658-23665. doi: 10.1007/s11356-017-0006-2. Epub 2017 Aug 31.
Sulfamethoxazole (SMX) was decomposed by using gamma irradiation in the presence of different additives such as NO, NO, Cr(VI), 2-propanol, and tert-butanol. The results demonstrated that NO, NO, 2-propanol, and tert-butanol inhibited SMX radiolytic removal. However, there existed a synergetic effect for radiolytic removal of the mixture containing SMX and Cr(VI). At an absorbed dose of 150 Gy, the removal percentages of SMX and Cr(VI) in the mixture were 73.5 and 84.6%, respectively, which was higher than the removal percentages of 70.6 and 4.1% for the single component of SMX and Cr(VI). This provides us an insight into treating the combined pollution in micro-polluted water. The SMX radiolytic removal followed a pseudo first-order reaction kinetic model, and the rate constant ratios of ·OH, e, and H· towards SMX radiolysis were 10.4:1:2.9. In addition, 24-h bio-inhibitory to the macroalgae of SMX solution during gamma irradiation reached the maximum of 0.85 at an adsorbed dose of 100 Gy, then gradually decreased with the increasing adsorbed dose. Based on LC-MS analysis and quantum chemical calculation, the degradation intermediates were determined and concluded that SMX radiolytic removal was mainly via ·OH radical attack and direct decomposition of SMX molecule by gamma ray.
磺胺甲恶唑（SMX）在不同添加剂如 NO、NO、Cr(VI)、2-丙醇和叔丁醇的存在下通过γ辐照进行分解。结果表明，NO、NO、2-丙醇和叔丁醇抑制了 SMX 的辐射分解去除。然而，对于含有 SMX 和 Cr(VI)的混合物，存在辐射分解去除的协同效应。在吸收剂量为 150 Gy 时，混合物中 SMX 和 Cr(VI)的去除率分别为 73.5%和 84.6%，高于 SMX 和 Cr(VI)单一组分的去除率 70.6%和 4.1%。这为我们处理微污染水中的联合污染提供了新的思路。SMX 的辐射分解遵循拟一级反应动力学模型，·OH、e 和 H·对 SMX 辐射分解的速率常数比为 10.4:1:2.9。此外，在 γ 辐照过程中，SMX 溶液对大型藻类的 24 小时生物抑制作用在吸收剂量为 100 Gy 时达到最大值 0.85，然后随着吸收剂量的增加逐渐降低。基于 LC-MS 分析和量子化学计算，确定了降解中间产物，并得出结论，SMX 的辐射分解去除主要是通过·OH 自由基攻击和γ射线直接分解 SMX 分子。
