Amino-modified metal-organic frameworks as peroxymonosulfate catalyst for bisphenol AF decontamination: ROS generation, degradation pathways, and toxicity evaluation

Advanced oxidation processes (AOPs) based on the metal-organic frameworks (MOFs) and peroxymonosulfate (PMS) have been demonstrated as promising methods for the degradation of contaminants. In this study, the degradation of bisphenol AF (BPAF) by activated PMS via amino-modified metal-organic frameworks (AMOF) was investigated thoroughly. BPAF could be efficiently removed (94.1%) in the optimal condition. The decontamination of BPAF could be accelerated significantly with the increasing temperature, and a highly stable degradation performance was observed at a wide pH range. Quenching experiments and electron paramagnetic resonance (EPR) tests revealed that sulfate radical (SO4-center dot), hydroxyl radical (HO center dot), singlet oxygen (1O2), and superoxide radical (O2-center dot) were produced synergistically in the AMOF/PMS system. Chloride ion (Cl-) exhibited a dual influence on BPAF removal, while other anions and NOM could hinder the degradation rate mildly. A total of fifty-two intermediates were identified using UHPLC-MS/MS method and four main degradation pathways were proposed based on the density functional theory (DFT) calculation, including the frontier molecular orbital theory (FMO), natural population analysis (NPA), and Fukui function. Finally, the Quantitative Structure Activity Relationship (QSAR) method for Toxicity Estimation Software Tool (TEST) was applied to estimate the accurate toxicity of BPAF and degradation byproducts. This study exhibited the promising potential for the decontamination of BPAF in the water via the AMOF based AOPs.

Automated summary

The study explored the efficient degradation of bisphenol AF (BPAF) through activated peroxymonosulfate (PMS) using amino-modified metal-organic frameworks (AMOF) with promising potential for water decontamination. The degradation performance of BPAF was stable over a wide pH range, accelerating with increasing temperature, producing multiple radicals synergistically in the AMOF/PMS system. The study identified fifty-two intermediates and proposed four main degradation pathways, utilizing advanced techniques such as density functional theory (DFT) calculation and Quantitative Structure Activity Relationship (QSAR) for toxicity estimation of BPAF and its degradation byproducts.