硅藻土负载MnFe2O4纳米颗粒活化PMS降解金橙Ⅱ

采用溶胶-凝胶法制备硅藻土/MnFe₂O₄复合型催化剂（DMF），以金橙Ⅱ为目标污染物，分析DMF活化过一硫酸盐（PMS）的性能和作用机制。结果表明:1） MnFe₂O₄颗粒均匀负载于硅藻土上，使DMF具有更好的分散性和活化性；2） DMF对PMS的活化能力优于单一MnFe₂O₄，DMF （1:1）/PMS体系降解金橙Ⅱ符合准一级动力学模型，且降解速率是MnFe₂O₄/PMS体系的2.16倍，0.5 g/L DMF和0.5 mmol/L PMS在40 min内对50 mg/L金橙Ⅱ降解率达到93.1%；3）反应体系中存在·OH、SO₄-·、1O₂、·O₂- 4种活性物种，其中·OH和SO₄-·起主导作用；4） DMF复合材料具有更好的结构稳定性，金属离子溶出量远低于MnFe₂O₄。研究结果可为新型高效PMS催化剂在处理工业废水的实际应用提供参考。

NANOPARTICLES SUPPORTED BY DIATOMITE FOR REMOVAL OF ORANGE Ⅱ THROUGH ACTIVATING PMS

Diatomite/MnFe₂O₄ composite catalyst (DMF) was rationally synthesized by sol-gel method. The performance and reaction mechanism of DMF activated peroxymonosulfate (PMS) were degraded with orange Ⅱ as the target pollutant. The results showed that:1) MnFe₂O₄ particles were uniformly loaded on diatomite and DMF had better dispersion and stability; 2) DMF had a better catalytic activity to PMS than MnFe₂O₄ so that the degradation rate of DMF/PMS system for orange Ⅱ removal was 2.16 times that of MnFe₂O₄ system, the reaction process could be fitted by the pseudo-first-order kinetic pattern. A degradation rate of 93.1% could be achieved within 40 min for 50 mg/L AO₂ by 0.5 g/L DMF and 0.5 mmol/L PMS; 3) there were four active radicals ·OH、SO₄-·、1O₂ and ·O₂- in the reaction system, and OH and SO₄- play the main role; 4) DMF had better structural stability and its metal ion dissolution was much lower than MnFe₂O₄. This study paved a way for the practical application of the new PMS activators in industrial wastewater treatment.