Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084, PR China.
Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, Tsinghua University, Beijing 100084, PR China.
Sci Total Environ. 2019 Jun 10;668:67-73. doi: 10.1016/j.scitotenv.2019.03.027. Epub 2019 Mar 4.
Sulfamethoxazole (SMX) is a widespread and persistent antibiotic pollutant in the aquatic environment. In this paper, SMX was degraded by gamma irradiation, and various influencing factors were explored. The experimental results revealed that after 1.5 kGy irradiation, 20 mg/L SMX could be completely decomposed. Kinetics studies suggested that the radiation-induced degradation process of SMX conformed first-order kinetic. The pH value had influence on the decomposition efficiency through changing the species of reactive radicals and the existing form of SMX molecules and their distribution. Additionally, the effect of inorganic anions (CO, HCO, NO, SO, Cl, HPO) and organic matters (peptone, glucose, humic acid) on SMX degradation was evaluated, which had negative influence on SMX degradation. The degradation efficiency of SMX decreased in the effluent water of WWTP in comparison with that in deionized water, suggesting that the components in the effluent inhibited the radiation-induced decomposition of SMX. The mineralization of SMX by ionizing radiation was also evaluated. These results revealed that ionizing radiation is a promising technology to degrade SMX in aqueous solution as well as in wastewater.
磺胺甲恶唑（SMX）是一种在水环境中广泛存在且具有持久性的抗生素污染物。本文采用γ射线辐照降解磺胺甲恶唑，探讨了各种影响因素。实验结果表明，1.5kGy 辐照后，20mg/L 的磺胺甲恶唑可完全分解。动力学研究表明，SMX 的辐射诱导降解过程符合一级动力学。pH 值通过改变反应性自由基的种类、SMX 分子的存在形式及其分布，对分解效率有影响。此外，还评估了无机阴离子（CO、HCO、NO、SO、Cl、HPO）和有机物（蛋白胨、葡萄糖、腐殖酸）对 SMX 降解的影响，它们对 SMX 降解有负面影响。与去离子水相比，在废水处理厂的出水（effluent water）中 SMX 的降解效率降低，表明废水中的成分抑制了 SMX 的辐射诱导分解。还评估了离子辐射对 SMX 的矿化作用。这些结果表明，离子辐射是一种很有前途的技术，可以降解水溶液和废水中的 SMX。
