School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian, 116024, China.
School of Environmental Science and Technology, Dalian University of Technology, Linggong Road 2, Dalian, 116024, China.
Chemosphere. 2021 Oct;281:130895. doi: 10.1016/j.chemosphere.2021.130895. Epub 2021 May 17.
A non-radical catalytic ozonation process functionalized by Mn(II)-sites was found effective to degrade oxalic acid as a typical refractory compound that is hard to remove through catalytic ozonation with hydroxyl radical oxidation. Specifically, we prepared functional Mn-C@Fe nanoparticles with carbon shell supporting MnO for catalysis while encapsulating magnetic iron core for recycle. Batch study shows its excellent catalytic reactivity on the degradation of organics particular for the ozone-recalcitrant oxalic acid (20 min for 90.9% removal, kinetics constant of 0.045 min). Our mechanism study ruled out the hydroxyl radical oxidation, and highlighted the formation of a heptavalent Mn intermediate oxidant responsible for the fast degradation that was initiated via ozone activation of Mn(II)-sites on the carbon shell. Our findings underscore a non-radical catalytic ozonation as a promising alternative technology for the abatement of aqueous organic pollutants.
我们发现，一种通过 Mn(II)位功能化的非自由基催化臭氧化过程对于降解草酸非常有效，因为草酸是一种典型的难去除的难处理化合物，通过羟基自由基氧化的催化臭氧化很难将其去除。具体来说，我们制备了具有碳壳支撑 MnO 的功能化 Mn-C@Fe 纳米粒子，用于催化，同时封装磁性铁核以进行回收。批处理研究表明，它在有机物降解方面具有优异的催化活性，特别是对于臭氧难处理的草酸（20 分钟去除 90.9%，动力学常数为 0.045 分钟）。我们的机理研究排除了羟基自由基氧化，并强调了形成七价 Mn 中间氧化剂，该氧化剂负责快速降解，这是通过碳壳上 Mn(II)位的臭氧活化引发的。我们的研究结果强调了非自由基催化臭氧化作为一种有前途的替代技术，用于去除水中的有机污染物。
