School of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao, 066004, China.
Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse, Qinhuangdao, 066004, China.
Environ Sci Pollut Res Int. 2021 Aug;28(29):39513-39523. doi: 10.1007/s11356-021-13551-z. Epub 2021 Mar 23.
Magnesium oxide/expanded graphite (MgO/EG) catalyst was synthesized and applied for enhancing the degradation of Cu-ethylenediaminetetraacetic acid (Cu-EDTA) in an aqueous solution. The MgO/EG catalyst was characterized by XRD, SEM, EDS, and FTIR. For assessing the catalytic activity of MgO/EG, essential influencing factors were investigated including catalyst dosage, O dosage, initial pH, initial Cu-EDTA concentration, and coexisting ions. The results show that the catalytic material showed high catalytic oxidation capacity for the Cu-EDTA removal in the MgO/EG/O system. 100% of Cu(II) and 73.2% of TOC removal efficiency could be achieved in the MgO/EG/O system at the reaction times of 90 min. This efficiency was higher than that seen for other systems, including O alone (Cu(II) 81.4%/TOC 60.6%), EG/O (84.2%/64.1), MgO/EG (< 4%/< 4%), and EG (< 4%/< 4%). A small decrease in the Cu(II) and TOC removal rate was observed after three runs in the stability and reusability experiments of the catalyst. Assays with radical scavenging experiments confirmed that MgO/EG-mediated oxidation was dependent on a hydroxyl radical pathway. The UV-vis spectra confirmed that the absorption peak of Cu-EDTA was gradually decreased and finally disappeared.
氧化镁/膨胀石墨（MgO/EG）催化剂被合成并应用于增强水溶液中 Cu-乙二胺四乙酸（Cu-EDTA）的降解。MgO/EG 催化剂通过 XRD、SEM、EDS 和 FTIR 进行了表征。为了评估 MgO/EG 的催化活性，研究了包括催化剂用量、O 用量、初始 pH 值、初始 Cu-EDTA 浓度和共存离子在内的基本影响因素。结果表明，在 MgO/EG/O 体系中，催化材料对 Cu-EDTA 的去除具有很高的催化氧化能力。在 90 分钟的反应时间内，MgO/EG/O 体系中 Cu(II)的去除率达到 100%，TOC 的去除率达到 73.2%。与其他体系相比，这一效率更高，包括单独的 O（Cu(II)81.4%/TOC60.6%）、EG/O（84.2%/64.1%）、MgO/EG（<4%/<4%）和 EG（<4%/<4%）。在催化剂的稳定性和重复使用实验中，经过三次运行后，Cu(II)和 TOC 去除率略有下降。自由基清除实验表明，MgO/EG 介导的氧化依赖于羟基自由基途径。紫外-可见光谱证实了 Cu-EDTA 的吸收峰逐渐降低，最终消失。
