School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, PR China.
School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, PR China; The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Cluster Ministry of Education, Guangzhou 510006, PR China; Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, Guangzhou 510006, PR China.
J Hazard Mater. 2020 Dec 5;400:123157. doi: 10.1016/j.jhazmat.2020.123157. Epub 2020 Jun 20.
Novel nano zero-valent iron anchored bio-matrix supported CoO (nZVI/yCoO) composites were fabricated for tetracycline (TC) efficient degradation by activating peroxydisulfate (PS). The systematical characterizations verified that the nZVI/yCoO composites with magnetism have higher surface area than yCoO and pure CoO, contributing to more accessible active sites. Various catalytic parameters (nZVI mass ratio, leached ions, initial pH, catalyst dosage, PS concentration and coexisting anions) were thoroughly investigated. In nZVI/yCoO/PS system, 97.6 %, 93.4 % and 77.3 % TC were degraded within 15 min at pH 3.0, 6.0 and 9.0, respectively. Based on four successive degradation runs, the excellent mineralization rate and reusability of nZVI/yCoO composites were mainly benefited from the suppressed metals leaching. The PS activated mechanisms were proposed as non-radicals (O) dominated pattern at acidic conditions and radicals (SO-) predominant pattern at alkaline environment, which may be highly related to the electron donating capacity of nZVI at different pH and the M/M redox cycling between Fe or Co metal. The plausible degradation routes of TC were presented based on the detected intermediates. Overall, the synthesized heterogeneous nZVI/yCoO composites can efficiently active PS at a wide pH range, and further broaden the application of Co-based catalysts in PS activation.
新型纳米零价铁锚定生物基质负载 CoO(nZVI/yCoO)复合材料通过激活过二硫酸盐(PS)被用于高效降解四环素(TC)。系统的特性验证了具有磁性的 nZVI/yCoO 复合材料比 yCoO 和纯 CoO 具有更高的表面积，这有助于提供更多的可用活性位点。研究了各种催化参数(nZVI 质量比、浸出离子、初始 pH 值、催化剂用量、PS 浓度和共存阴离子)。在 nZVI/yCoO/PS 体系中，在 pH 值为 3.0、6.0 和 9.0 时，分别在 15 min 内降解了 97.6%、93.4%和 77.3%的 TC。基于四次连续降解实验，nZVI/yCoO 复合材料具有优异的矿化率和可重复使用性，主要得益于抑制了金属浸出。提出了 PS 激活机制为酸性条件下以非自由基(O)为主和碱性条件下以自由基(SO-)为主，这可能与不同 pH 值下 nZVI 的电子供体能力以及 Fe 或 Co 金属之间的 M/M 氧化还原循环密切相关。根据检测到的中间产物，提出了 TC 的可能降解途径。总的来说，合成的异质 nZVI/yCoO 复合材料可以在很宽的 pH 范围内有效激活 PS，并进一步拓宽 Co 基催化剂在 PS 激活中的应用。
