Atmospheric Environment, Год журнала: 2023, Номер 307, С. 119843 - 119843
Опубликована: Май 15, 2023
Язык: Английский
Опубликована: Янв. 2, 2024
The total oxidizable precursor (TOP) assay has been extensively used for detecting PFAS pollutants without analytical standards. It uses hydroxyl radical (HO•) from the heat-activation of persulfate under alkaline pH to convert H-containing precursors perfluorocarboxylates (PFCAs) target analysis. However, current TOP oxidation method does not apply emerging because (i) many structures do contain C−H bonds HO• attack, and (ii) transformation products are necessarily PFCAs. In this study, we explored use classic acidic digestion, which generates sulfate (SO4−•), extend capability assay. We examined Nafion-related ether sulfonates that or −COO−, characterized products, quantified F atom balance. SO4−• greatly expanded scope precursors. was initiated by decarboxylation, followed various spontaneous steps such as HF elimination ester hydrolysis. further compared legacy fluorotelomers using versus HO•. results suggest novel product distribution patterns depending on functional group oxidant dose. Therefore, (1) combined oxidation, (2) list standard chemicals, (3) elucidation mechanisms will provide more critical information probe structures.
Язык: Английский
Процитировано
1
Emerging contaminants, Год журнала: 2024, Номер 10(2), С. 100301 - 100301
Опубликована: Янв. 26, 2024
The electroplating industry is the main source of 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA) pollution, which presents risks to human health and environment. It therefore crucial develop effective Cl-PFESA degradation techniques. Persulfate oxidation a potential treatment method for due its outstanding oxidative degradability following generation sulfate radical (SO4•−) hydroxyl (•OH). has proven difficult acquire full understanding reaction mechanism formation intermediate (IM) products through conventional experimental studies because they are costly time-consuming. Therefore, theoretical analysis based on density functional theory (DFT) calculations was applied. DFT results showed that electron transfer could be initiated by protonated (HSO4•, ΔG≠SET = 9.16 kcal/mol), rather than SO4•− (ΔG≠SET 41.60 kcal/mol). After desulfonation, underwent stepwise decarboxylation cycles under action •OH, leading elimination CF2 units until there complete mineralization into HCl, HF, CO2. Furthermore, IMs end were evaluated using ECOSAR TEST software. low bioaccumulation short-chain meant considered safe in terms ecotoxicity effects. This research determined mechanistic basis effects persulfate water containing Cl-PFESA, structural analogues.
Язык: Английский
Процитировано
1
Toxics, Год журнала: 2024, Номер 12(3), С. 207 - 207
Опубликована: Март 9, 2024
Persulfate-based advanced oxidation process has been proven to be a promising method for the toxic pesticide chlorpyrifos (CPY) degradation in wastewater treatment. However, due limitation short-lived intermediates detection, comprehensive understanding pathway remains unclear. To address this issue, density functional theory was used analyze mechanism of CPY at M06-2X/6-311++G(3df,3pd)//M06-2X/6-31+G(d,p) level, and computational toxicology methods were employed explore toxicity its products. Results show that hydroxyl radicals (·OH) sulfate (SO4•−) initiate reactions by adding P=S bond abstracting H atom on ethyl group, rather than undergoing α-elimination pyridine ring persulfate process. Moreover, addition products attracted degraded breaking P–O bond, while abstraction through dealkylation reactions. The transformation products, including 3,5,6-trichloro-2-pyridynol, O,O-diethyl phosphorothioate, oxon, acetaldehyde, obtained theoretical calculations have detected previous experimental studies. reaction rate constants with ·OH SO4•− 6.32 × 108 9.14 M−1·s−1 room temperature, respectively, which consistent values 4.42 109 4.5 M−1 s−1. Toxicity evaluation results indicated acute chronic aquatic organisms gradually decreased during some still possess or highly levels, may pose risks human health. These research findings contribute behavior risk assessment practical
Язык: Английский
Процитировано
1
RSC Advances, Год журнала: 2024, Номер 14(42), С. 30582 - 30589
Опубликована: Янв. 1, 2024
The advanced oxidation process based on persulfate has been proven to be a promising method for degrading the highly toxic carbamate pesticide carbofuran (CBF).
Язык: Английский
Процитировано
1
Atmospheric Environment, Год журнала: 2023, Номер 307, С. 119843 - 119843
Опубликована: Май 15, 2023
Язык: Английский
Процитировано
2