Tailoring the selective generation of oxidative organic radicals for toxic-by-product-free water decontamination

Proceedings of the National Academy of Sciences, Год журнала: 2024, Номер 121(23)

Опубликована: Май 28, 2024

Peracetic acid (PAA) is emerging as a versatile agent for generating long-lived and selectively oxidative organic radicals (R–O • ). Currently, the conventional transition metal–based activation strategies still suffer from metal ion leaching, undesirable by-products formation, uncontrolled reactive species production. To address these challenges, we present method employing BiOI with unique electron structure PAA activator, thereby predominantly CH 3 C(O)O radicals. The specificity of generation ensured superior performance BiOI/PAA system across wide pH range (2.0 to 11.0), even in presence complex interfering substances such humic acids, chloride ions, bicarbonate real-world water matrices. Unlike catalytic methods, degrades sulfonamides without producing any toxic by-products. Our findings demonstrate advantages decontamination pave way development eco-friendly decontaminations based on peroxides.

Язык: Английский

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Comprehensive Insight into the Common Organic Radicals in Advanced Oxidation Processes for Water Decontamination

Environmental Science & Technology, Год журнала: 2024, Номер 58(44), С. 19571 - 19583

Опубликована: Окт. 23, 2024

Radical-based advanced oxidation processes (AOPs) are among the most effective technologies employed to destroy organic pollutants. Compared common inorganic radicals, such as

Язык: Английский

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CoFe2O4@BC as a heterogeneous catalyst to sustainably activate peroxymonosulfate for boosted degradation of enrofloxacin: Properties, efficiency and mechanism

Separation and Purification Technology, Год журнала: 2024, Номер 345, С. 127349 - 127349

Опубликована: Апрель 3, 2024

Язык: Английский

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Peroxydisulfate-Driven Reductive Dechlorination as Affected by Soil Constituents: Free Radical Formation and Conversion

Environmental Science & Technology, Год журнала: 2024, Номер 58(18), С. 8065 - 8075

Опубликована: Апрель 10, 2024

We report a previously unrecognized but efficient reductive degradation pathway in peroxydisulfate (PDS)-driven soil remediation. With supplements of naturally occurring low-molecular-weight organic acids (LMWOAs) anaerobic biochar-activated PDS systems, rates 12 γ-hexachlorocyclohexanes (HCH)-spiked soils boosted from 40% without LMWOAs to maximum 99% with 1 mM malic acid. Structural analysis revealed that an increase α-hydroxyl groups and diminution pKa1 values facilitated the formation carboxyl anion radicals (COO•–) via electrophilic attack by SO4•–/•OH. Furthermore, kinetics were strongly correlated matter (SOM) contents than iron minerals. Combining newly developed situ fluorescence detector quenching experiments, we showed for high, medium, low SOM contents, dominant reactive species switched singlet oxygen/semiquinone SO4•–/•OH then COO•– (contribution increased 30.8 66.7%), yielding superior HCH degradation. Validation experiments using model compounds highlighted critical roles redox-active moieties, such as phenolic – OH quinones, radical conversion. Our study provides insights into environmental behaviors related activation persulfate broader horizon inspiration more advanced reduction technologies.

Язык: Английский

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Unraveling the Role of Humic Acid in the Oxidation of Phenolic Contaminants by Soluble Manganese Oxo-Anions

Environmental Science & Technology, Год журнала: 2024, Номер 58(19), С. 8576 - 8586

Опубликована: Май 2, 2024

Humic acid (HA) is ubiquitous in natural aquatic environments and effectively accelerates decontamination by permanganate (Mn(VII)). However, the detailed mechanism remains uncertain. Herein, intrinsic mechanisms of HA's impact on phenolics oxidation Mn(VII) its intermediate manganese oxo-anions were systematically studied. Results suggested that HA facilitated transfer a single electron from Mn(VII), resulting sequential formation Mn(VI) Mn(V). The formed Mn(V) was further reduced to Mn(III) through double process HA. responsible for HA-boosted as active species attacking pollutants, while tended act due their own instability. In addition, could serve stabilizer form complex with produced retard disproportionation Mn(III). Notably, did not mineralize but essentially changed composition. According results Fourier-transform ion cyclotron resonance mass spectrometry second derivative analysis infrared spectroscopy, we found triggered decomposition C–H bonds subsequently oxygen-containing functional groups (i.e., C–O). This study might shed new light HA/manganese oxo-anion process.

Язык: Английский

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Overlooked Complexation and Competition Effects of Phenolic Contaminants in a Mn(II)/Nitrilotriacetic Acid/Peroxymonosulfate System: Inhibited Generation of Primary and Secondary High-Valent Manganese Species

Environmental Science & Technology, Год журнала: 2024, Номер 58(42), С. 19080 - 19089

Опубликована: Сен. 14, 2024

Organic contaminants with lower Hammett constants are typically more prone to being attacked by reactive oxygen species (ROS) in advanced oxidation processes (AOPs). However, the interactions of an organic contaminant catalytic centers and participating ROS complex lack in-depth understanding. In this work, we observed abnormal phenomenon AOPs that degradation electron-rich phenolics, such as 4-methoxyphenol, acetaminophen, 4-presol, was unexpectedly slower than electron-deficient phenolics a Mn(II)/nitrilotriacetic acid/peroxymonosulfate (Mn(II)/NTA/PMS) system. The established quantitative structure-activity relationship revealed volcano-type dependence rates on pollutants. Leveraging substantial analytical techniques modeling analysis, concluded would inhibit generation both primary (Mn(III)NTA) secondary (Mn(V)NTA) high-valent manganese through complexation competition effects. Specifically, form hydrogen bond Mn(II)/NTA/PMS outer-sphere interactions, thereby reducing electrophilic reactivity PMS accept electron transfer from Mn(II)NTA, slowing down Mn(III)NTA. Furthermore, generated Mn(III)NTA is inclined react due their higher reaction rate (8314 ± 440, 6372 146, 6919 31 M

Язык: Английский

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From Quencher to Promoter: Revisiting the Role of 2,4,6-Trimethylphenol (TMP) in Triplet-State Photochemistry of Dissolved Organic Matter

Environmental Science & Technology, Год журнала: 2025, Номер unknown

Опубликована: Фев. 25, 2025

Triplet-state dissolved organic matter (3DOM*) plays a crucial role in environmental aquatic photochemistry, with 2,4,6-trimethylphenol (TMP) frequently used as chemical probe or quencher due to its high reactivity 3DOM*. However, the influence of TMP-derived oxidation intermediates on target photochemical reactions has not been comprehensively examined. This study investigated TMP's effect photolysis sulfamethoxazole (SMX), common antibiotic found natural waters, presence different DOM sources model photosensitizer. Contrary expectation, TMP significantly accelerated SMX photolysis, extent enhancement depending and concentrations. Laser flash kinetic modeling suggested long-lived reactive species (TMP-RS), including phenoxyl radicals, semiquinone quinones, key factors this process. Unlike 3DOM*, TMP-RS may react formation non-SMX•+ intermediates. process prevents reduction SMX•+ subsequent regeneration SMX. The successfully predicts dynamic contributions various during reaction, highlighting critical TMP-RS. advances our understanding involvement triplet-state photochemistry suggests reconsideration RSs play transformation micropollutants.

Язык: Английский

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Manganese oxide for heterogeneous Fenton treatment: Catalyst or inhibitor?

Applied Catalysis B Environment and Energy, Год журнала: 2024, Номер 359, С. 124531 - 124531

Опубликована: Авг. 24, 2024

Язык: Английский

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Facile synthesis of Cu-doped manganese oxide octahedral molecular sieve for the efficient degradation of sulfamethoxazole via peroxymonosulfate activation

International Journal of Minerals Metallurgy and Materials, Год журнала: 2024, Номер 31(12), С. 2770 - 2780

Опубликована: Авг. 29, 2024

Язык: Английский

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Semirational Design Strategy To Enhance the Thermostability and Catalytic Activity of Cytochrome P450 105D7 for the Degradation of the Pharmaceutically Active Compounds: Diclofenac

Environmental Science & Technology, Год журнала: 2024, Номер 58(35), С. 15681 - 15690

Опубликована: Апрель 26, 2024

Pharmaceutically active compounds are an important category of emerging pollutants, and their biological transformation processes in the environment crucial for understanding evaluating migration, transformation, environmental fate pollutants. The cytochrome P450 105 enzyme family has been proven to play role degradation exogenous However, its thermostability catalytic activity still need be improved better adapt complex conditions. This work elucidates key mechanisms residues reaction through multiple computational strategies, establishes a mutation library, obtains 21 single-point designs. Experimental verification showed that 16 single mutants had enhanced thermostability, with R89F L197Y showing highest increases at 135 119% relative wild-type enzyme, respectively. Additionally, as result higher specific D390Q, it was selected combination mutagenesis, ultimately resulting three (R89F/L197Y, R89F/D390Q, R89F/L197Y/D390Q) activity. study provides modification approach constructing efficient variants semirational design can contribute development control technologies

Язык: Английский

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