碳酸氢钠溶液中微量 Mn2+离子催化氧化降解有机污染物

 考察了微量 Mn2+离子在 NaHCO3 溶液中催化 H2O2 氧化降解有机污染物的性能. 结果表明, NaHCO3, MnCl2 和 H2O2 浓度分别为 25, 0.1 和 100 mmol/L 时, 在 25 oC 下反应 180 min 后亚甲基蓝可完全脱色, 化学耗氧量和总有机碳去除率分别达到 44.0% 和 13.8%. 该催化体系对甲基橙、罗丹明 B 以及垃圾渗滤液等都有较好去除效果. 紫外-可见光谱分析及反应动力学测试表明, MnIV=O 是该催化体系主要活性物种.

Oxidative Degradation of Organic Pollutants Catalyzed by Trace Manganese(II) Ion in Sodium Bicarbonate Solution

Catalytic degradation of organic pollutants in a sodium bicarbonate solution with Mn2+ ion (0.004–0.1 mmol/L) as the catalyst has been studied using H2O2 as the oxidant. Complete decoloration of methylene blue was achieved in 180 min with 44.0% chemical oxidation demand removal at 25 oC at the NaHCO3, MnCl2 and H2O2 concentrations of 25, 0.1, and 100 mmol/L, respectively. The total organic carbon measurement indicated that 13.8% of the carbon was mineralized. The Mn2+/HCO3? + H2O2 system also showed high ability for oxidative degradation of methyl orange, rhodamine B, and even landfill leachate. The analysis of UV-Vis spectroscopy and reaction kinetics indicated that the MnIV=O intermediate is the key active species in methylene blue degradation.