Mai Jiamin, Zeng Ge, Jiang Maoju, Su Peng, Lv Qixiao, Li Wenqi, Hou Xiangyang, Liu Minchao, Ma Jun, Yang Tao
Jiangmen Key Laboratory of Synthetic Chemistry and Cleaner Production, School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, Guangdong Province, China.
State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Sci Total Environ. 2024 Sep 20;944:173655. doi: 10.1016/j.scitotenv.2024.173655. Epub 2024 Jun 6.
A novel approach of visible light-emitting diode (Vis-LED) radiation was employed to activate permanganate (Mn(VII)) for efficient organic micropollutant (OMP) removal. The degradation rates of OMPs by Vis-LED/Mn(VII) were 2-5.29 times higher than those by Mn(VII) except for benzoic acid and atrazine. Increasing wavelengths (445-525 nm) suppressed the degradation of diclofenac (DCF) and 4-chlorophenol (4-CP) owing to the decreased quantum yields of Mn(VII). Comparatively, light intensity and Mn(VII) dosage had a positive effect on the degradation of DCF and 4-CP. Experimental data revealed that Mn(V) dominated the DCF degradation whereas Mn(III) was the active oxidant in the 4-CP degradation. Mn(V) and Mn(III) formed from the photo-decomposition of Mn(VII), meanwhile, Mn(III) also formed from the Mn(V) photo-decomposition. The increase in solution pH inhibited DCF degradation but had a positive impact on 4-CP degradation, mainly due to the changing speciation of DCF and 4-CP. Inorganic anions (Cl and HCO) had little impact on DCF and 4-CP degradation, while humic acid (HA) showed a positive impact because of the π-π interaction between HA and DCF/4-CP. The transformation products of DCF and 4-CP were identified and transformation pathways were proposed. Finally, the Vis-LED/Mn(VII) exhibited great degradation performance in various authentic waters. Overall, this study boosts the development of Mn(VII)-based oxidation processes.
采用一种新型的可见光发光二极管（Vis-LED）辐射方法来激活高锰酸盐（Mn(VII)），以高效去除有机微污染物（OMP）。除苯甲酸和阿特拉津外，Vis-LED/Mn(VII)对OMP的降解率比Mn(VII)高2至5.29倍。由于Mn(VII)的量子产率降低，增加波长（445 - 525 nm）会抑制双氯芬酸（DCF）和4-氯酚（4-CP）的降解。相比之下，光强和Mn(VII)用量对DCF和4-CP的降解有积极影响。实验数据表明，Mn(V)主导DCF的降解，而Mn(III)是4-CP降解中的活性氧化剂。Mn(V)和Mn(III)由Mn(VII)的光分解形成，同时，Mn(III)也由Mn(V)的光分解形成。溶液pH值的升高抑制了DCF的降解，但对4-CP的降解有积极影响，这主要是由于DCF和4-CP的形态变化。无机阴离子（Cl和HCO）对DCF和4-CP的降解影响不大，而腐殖酸（HA）由于其与DCF/4-CP之间的π-π相互作用而表现出积极影响。确定了DCF和4-CP的转化产物并提出了转化途径。最后，Vis-LED/Mn(VII)在各种实际水体中表现出优异的降解性能。总体而言，本研究推动了基于Mn(VII)的氧化工艺的发展。
