School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, Guangdong, China.
School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou, 510006, Guangdong, China.
Environ Res. 2022 Nov;214(Pt 1):113778. doi: 10.1016/j.envres.2022.113778. Epub 2022 Jul 4.
Among homogeneous catalysts, cobalt ions exhibit ultra-high persulfate activation performance. In this work, an electrically supported medium Co(II) activated peroxydisulfate synergistic process was established to eliminate organic contaminants in water. The synergistic catalytic effect was verified by comparing the oxidative degradation performance and reaction rate constant of different coupling systems. The decolorization ability of E-Co(II)-PDS on reactive black 5 (RB5) was explored, and the results showed that the removal rate of RB5 can reach 93.21% under the optimized conditions of current density of 5.71 mA/cm, initial pH of 4, Co(II) concentration of 0.2 mM and PDS concentration of 5 mM. The effect of water matrix on the removal of RB5 was studied, and it was found that HCO and humic acid significantly inhibited the degradation of RB5, while Cl and HPO could effectively promote it at a certain concentration. Notably, the degradation of RB5 in E-Co(II)-PDS system achieved lower energy consumption, with an energy consumption per unit volume (EE/O) value of 0.4304 kWh·m. EPR test, quenching experiments and contribution rate analysis showed that the oxidation active species in E-Co(II)-PDS process were Co(III), sulfate radicals and hydroxyl radicals, and their oxidation contribution rates were 15.72%, 12.69% and 53.25%, respectively. Finally, the decomposition process of RB5 was proposed by the mass spectrometry results. The electric current promotes cobalt ion cycling and PDS activation through electron transfer, and induces Co(II) to promote the activation of PDS, which is the main mechanism of E-Co(II)-PDS system to achieve the robust degradation ability of RB5.
在均相催化剂中，钴离子表现出超高效的过硫酸盐活化性能。在这项工作中，建立了一种电支撑的 Co(II) 介导过一硫酸盐协同工艺，以去除水中的有机污染物。通过比较不同耦合体系的氧化降解性能和反应速率常数，验证了协同催化作用。探讨了 E-Co(II)-PDS 对偶氮黑 5（RB5）的脱色能力，结果表明，在电流密度为 5.71 mA/cm、初始 pH 值为 4、Co(II)浓度为 0.2 mM 和过一硫酸盐浓度为 5 mM 的优化条件下，RB5 的去除率可达 93.21%。研究了水基质对 RB5 去除的影响，发现 HCO 和腐殖酸显著抑制 RB5 的降解，而 Cl 和 HPO 在一定浓度下能有效促进其降解。值得注意的是，E-Co(II)-PDS 体系中 RB5 的降解实现了较低的能耗，单位体积能耗（EE/O）值为 0.4304 kWh·m。EPR 测试、猝灭实验和贡献率分析表明，E-Co(II)-PDS 过程中的氧化活性物质为 Co(III)、硫酸根自由基和羟基自由基，其氧化贡献率分别为 15.72%、12.69%和 53.25%。最后，根据质谱结果提出了 RB5 的分解过程。电流通过电子转移促进钴离子循环和过一硫酸盐活化，并诱导 Co(II)促进过一硫酸盐的活化，这是 E-Co(II)-PDS 体系实现 RB5 强降解能力的主要机制。
