Insight into the role of reactive species on catalyst surface underlying peroxymonosulfate activation by P-Fe 2 MnO 4 loaded on bentonite for trichloroethylene degradation

• Published in: Chemosphere (Oxford) 2024-04, p.141943
• Main Authors: Feng, Meiyun, Xu, Zhiqiang, Li, Jianan, Wang, Ning, Lin, Kuangfei, Zhang, Meng
• Format: Article
• Language: English
• ISSN: 1879-1298
• DOI: 10.1016/j.chemosphere.2024.141943

In this study, bentonite supporting phosphorus-doped Fe MnO (BPF) was synthesized and applied for PMS activation to degrade TCE. Morphology and structure characterization results indicated the successfully synthesized of BPF, and the BPF/PMS system not only featured high TCE removal (97.4%) but also high reaction rate constant (k  = 0.0554 min ) and PMS utilization (70.4%, k  = 0.0228 min ). According to the results of various experiments, massive oxygen vacancies on P-Fe MnO alter its charge balance and facilitate the electron transfer process named adjacent transfer (direct electron capture by adsorbed PMS from adjacent TCE). Mn(III) is the main adsorption site for PMS, and the hydroxyl groups on the catalyst (Fe sites of P-Fe MnO , Si and Al sites of bentonite) can also offer binding sites for PMS. The hydrogen-bonded PMS on Fe(III) and Mn(III) sites will subsequently accept the discharged electrons to generate free radicals and high-valent metal species. Meanwhile, electron loss of HSO - that chemically bonded to hydroxyl groups on bentonite will generate SO , which will further produce O through self-bonding. the active species on the catalyst surface contribute 65% of TCE degradation in the heterogeneous catalytic oxidation system.