School of Earth and Environment, Anhui University of Science and Technology, Huainan 232001, China; Research Center for Environmental Nanotechnology (ReCENT), State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
Research Center for Environmental Nanotechnology (ReCENT), State Key Laboratory of Pollution Control and Resource Reuse, School of Environment, Nanjing University, Nanjing 210023, China.
J Hazard Mater. 2023 Feb 5;443(Pt B):130281. doi: 10.1016/j.jhazmat.2022.130281. Epub 2022 Oct 29.
Nanosized spinel cobalt ferrite (CoFeO) shows high performance in peroxymonosulfate (PMS) activation for decontamination in water, but is yet challenged by the easily leached Co(II) with high toxicity. Herein, macroporous polystyrene resin is used as the support to improve the stability of CoFeO nanoparticles during PMS activation. CoFeO@S201 exerted high catalytic activity toward PMS activation for oxidation of 1-hydroxyethane 1,1-diphosphonic acid (HEDP), with the apparent rate normalized by Co content 38.2 times higher than that of the unsupported CoFeO. Meanwhile, one order of magnitude lower Co leaching (< 2.1 μg L) was detected during the catalytic oxidation. The Co(II)-PMS complex was the primary oxidant responsible for the oxidation of HEDP. The catalytic durability and stability of CoFeO@S201 for degradation of HEDP in actual wastewater were systematically evaluated in both batch and continuous-flow mode. It is found that the organic resin, which is often considered to be intolerant to oxidation, is rather stable during the non-radical process. The total cobalt leaching of the fresh CoFeO@S201 cannot be ignored in the 100-h continuous-flow run. In contrast, much lower cobalt leaching and slightly higher oxidation efficiency were observed for the regenerated CoFeO@S201, which might be due to the removal of unreactive and unstable Co sites on the surface in the first trial. The findings shed light on the potential of organic supports for improving the stability and activity of nanosized CoFeO and other nano-catalysts toward practical application.
纳米尖晶石钴铁氧体（CoFeO）在过一硫酸盐（PMS）激活方面表现出高的水净化性能，但仍面临着高毒性的易浸出 Co(II)的挑战。在此，大孔聚苯乙烯树脂被用作载体，以提高 CoFeO 纳米颗粒在 PMS 激活过程中的稳定性。CoFeO@S201 对 PMS 激活具有高催化活性，可用于 1-羟基乙烷 1,1-二膦酸（HEDP）的氧化，表观速率归一化的 Co 含量比无载体 CoFeO 高 38.2 倍。同时，在催化氧化过程中检测到 Co 浸出量低一个数量级（<2.1μg/L）。Co(II)-PMS 配合物是氧化 HEDP 的主要氧化剂。在批处理和连续流模式下，系统评估了 CoFeO@S201 在实际废水中降解 HEDP 的催化耐久性和稳定性。结果发现，通常被认为不耐氧化的有机树脂在非自由基过程中相当稳定。在 100 小时连续流运行中，新鲜 CoFeO@S201 的总钴浸出量不容忽视。相比之下，对于再生的 CoFeO@S201，观察到钴浸出量较低，氧化效率略有提高，这可能是由于在第一次试验中去除了表面上无活性和不稳定的 Co 位。这些发现为有机载体提高纳米 CoFeO 和其他纳米催化剂的稳定性和活性以用于实际应用提供了新的思路。
