Kinetic and mechanism study of UV/pre-magnetized-Fe0/oxalate for removing sulfamethazine
Kinetic and mechanism study of UV/pre-magnetized-Fe0/oxalate for removing sulfamethazine
复制标题
紫外/预磁化-Fe0+/草酸盐去除磺胺二甲嘧啶的动力学及机理研究
DOI：
10.1016/j.jhazmat.2020.122931
复制
发表时间：
2020-11-05
影响因子：
13.6
通讯作者：
Zhang, Ying
中科院分区：
文献类型：
--
作者：
Pan, Yuwei;Wang, Qi;Zhang, Ying
在本研究中，以预磁化的零价铁（pre - Fe - 0）为催化剂，利用草酸盐（Ox）的紫外光辐照光化学反应来降解磺胺二甲嘧啶（SMT）。磁场促进了零价铁中铁离子的释放，从而提高了UV/pre - Fe - 0/Ox体系中SMT和草酸盐的去除率。X射线光电子能谱表明，紫外光和草酸盐的存在促进了零价铁表面Fe³⁺向Fe²⁺的转化，进而增强了表面束缚羟基自由基（·OHsurf）的生成。草酸盐抑制了铁（氢）氧化物的形成，并增强了零价铁表面的羟基化。·OHsurf对SMT去除的贡献率主要为44%，而紫外直接光解和溶液中的羟基自由基对SMT去除的贡献率均约为28%。添加草酸盐的体系在SMT降解方面比添加磷酸、柠檬酸和乙二胺四乙酸的体系效率高得多，这极大地拓展了螯合修饰芬顿工艺及其处理效率。
In this study, UV irradiated photochemical reactions of oxalate (Ox) with premagnetized-Fe-0 (pre-Fe-0) as the catalyst was used to degrade sulfamethazine (SMT). Magnetic field promoted the release of iron ion from Fe-0 thus enhanced SMT and Ox removal in UV/pre-Fe-0/Ox process. X-ray photoelectron spectroscopy demonstrated that the presence of UV and Ox promoted the transformation of Fe3+ to Fe2+ on Fe-0, which enhanced the surface bound center dot OH (center dot OHsurf) generation. Ox inhibited the formation of iron (hydro)xides and enhanced the hydroxylation of Fe-0 surface. center dot OHsurf was mainly responsible for SMT removal (44%), while UV direct photolysis and center dot OH in the solution both caused around 28% SMT removal. The process with Ox exhibited much higher efficiency in SMT degradation than that added with H3PO4, citric acid and ethylenediaminetetraacetic acid, which greatly expanded the chelate-modified Fenton processes and their treatment efficiency.