Humic acid(HA) as a natural reducing ligand was employed to accelerate the Fenton and Fenton-like processes, however, the potential role of photosensitivity was overlooked. This research showed that HA exhibits more s...Humic acid(HA) as a natural reducing ligand was employed to accelerate the Fenton and Fenton-like processes, however, the potential role of photosensitivity was overlooked. This research showed that HA exhibits more significant promotion for levofloxacin(LVF) degradation under light conditions compared to darkness. The study also proposed a mechanism involving complexation and photosensitization interactions. A strong inhibitor of ethylenediaminetetraacetic acid confirmed that the formation of organic-iron complexes was crucial. Firstly, it was proposed that complexed iron has a lower redox potential than free iron, which may be responsible for accelerating electron transfer from iron to peroxydisulfate(PDS). The density functional theory(DFT) calculations confirmed that complexed iron has a lower reaction energy barrier for PDS activation. Additionally, the excited state substances(^(*)HA and ^(*)LVF) can transfer electrons to Fe(Ⅲ) and PDS, and the generation of HA/LVF-Fe(Ⅲ)-PDS can accelerate this process. These findings could offer fresh perspectives on the combined elimination of contaminants through natural organic compounds and light exposure.展开更多
基金supported by the Natural Science Foundation of China (No. 42107073)Central Guidance for Local Science and Technology Development Fund Projects (No. 2024ZYD0030)+1 种基金Natural Science Foundation of Sichuan Province (No. 2024NSFSC0130)the Sichuan Science and Technology Program (No. 2024NSFTD0014)。
文摘Humic acid(HA) as a natural reducing ligand was employed to accelerate the Fenton and Fenton-like processes, however, the potential role of photosensitivity was overlooked. This research showed that HA exhibits more significant promotion for levofloxacin(LVF) degradation under light conditions compared to darkness. The study also proposed a mechanism involving complexation and photosensitization interactions. A strong inhibitor of ethylenediaminetetraacetic acid confirmed that the formation of organic-iron complexes was crucial. Firstly, it was proposed that complexed iron has a lower redox potential than free iron, which may be responsible for accelerating electron transfer from iron to peroxydisulfate(PDS). The density functional theory(DFT) calculations confirmed that complexed iron has a lower reaction energy barrier for PDS activation. Additionally, the excited state substances(^(*)HA and ^(*)LVF) can transfer electrons to Fe(Ⅲ) and PDS, and the generation of HA/LVF-Fe(Ⅲ)-PDS can accelerate this process. These findings could offer fresh perspectives on the combined elimination of contaminants through natural organic compounds and light exposure.
