College of Chemistry and Materials Science, Hengyang Normal University, Hengyang, 421008, People's Republic of China.
Key Laboratory of Functional Metal-Organic Compounds of Hunan Province, Hengyang, 421008, People's Republic of China.
Environ Sci Pollut Res Int. 2023 Oct;30(47):104505-104519. doi: 10.1007/s11356-023-29287-x. Epub 2023 Sep 13.
The development of heterogeneous Co-based catalysts with an effective combination mode of Co/Fe and supporter, a facile synthetic method, and a low treatment cost is an important environment challenge for azo dyes degradation by peroxymonosulfate (PMS) activation. In this study, NaA zeolite supported CoFe with various molar ratio of Fe/Si and Co/Fe was synthesized by a facile hydrothermal process, and used to activate PMS for Acid Orange 7 (AO7) degradation. NaA zeolite supported CoFe with the Fe/Si molar ratio of 1:10 showed superior catalytic performance compared with other NaA zeolite supported CoFe. In a system containing 0.6 g/L catalysts, 4 mM PMS, pH 5 and T = 30℃, 95.8% AO7 and 79.1% COD conversion could be achieved at 20 and 60 min, respectively, and the first order kinetic rate constant reached 0.14795 min. Moreover, NaA zeolite supported CoFe/PMS system exhibited excellent catalytic effect in a wide pH range of 3-9. Temperature had an obvious effect on AO7 degradation, and the activation energy was 31.36 kJ/mol. HCO demonstrated an obvious depression on AO7 degradation, while Cl, SO and HPO had a relatively poor impact. Quenching experiments showed that both sulfate radicals ([Formula: see text]) and hydroxyl radicals (·OH) were generated in the PMS reaction system, and the [Formula: see text] was the dominant active radical. During 3 cycles experiments, an acceptable AO7 conversion ratio (91.8%) within 30 min arrived, suggesting the good stability of NaA zeolite supported CoFe.
具有有效 Co/Fe 组合方式和载体的异质 Co 基催化剂的开发、简便的合成方法和低处理成本是通过过一硫酸盐 (PMS) 活化降解偶氮染料的重要环境挑战。在这项研究中，通过简便的水热法合成了具有不同 Fe/Si 摩尔比和 Co/Fe 摩尔比的 NaA 沸石负载 CoFe，并将其用于活化 PMS 降解酸性橙 7 (AO7)。与其他 NaA 沸石负载 CoFe 相比，具有 1:10 的 Fe/Si 摩尔比的 NaA 沸石负载 CoFe 表现出优越的催化性能。在包含 0.6 g/L 催化剂、4 mM PMS、pH 5 和 T = 30℃的体系中，在 20 和 60 min 时可以分别实现 95.8%的 AO7 和 79.1%的 COD 转化率，并且一级动力学速率常数达到 0.14795 min。此外，NaA 沸石负载 CoFe/PMS 体系在 3-9 的宽 pH 范围内表现出优异的催化效果。温度对 AO7 降解有明显的影响，活化能为 31.36 kJ/mol。HCO 对 AO7 降解有明显的抑制作用，而 Cl、SO 和 HPO 则有相对较差的影响。猝灭实验表明，在 PMS 反应体系中生成了硫酸盐自由基 ([Formula: see text]) 和羟基自由基 (·OH)，[Formula: see text]是主要的活性自由基。在 3 次循环实验中，在 30 min 内达到了可接受的 AO7 转化率（91.8%），表明 NaA 沸石负载 CoFe 具有良好的稳定性。
