Redox Oscillations Activate Thermodynamically Stable Iron Minerals for Enhanced Reactive Oxygen Species Production

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(23), P. 8628 - 8637

Published: May 31, 2023

Reactive oxygen species (ROS) play key roles in driving biogeochemical processes. Recent studies have revealed nonphotochemical electron transfer from redox-active substances (e.g., iron minerals) to as a new route for ROS production. Yet, naturally occurring minerals mainly exist thermodynamically stable forms, restraining their potential Here, we report that tide-induced redox oscillations can activate enhanced •OH production intertidal soils (15.8 ± 0.5 μmol/m2) was found be 5.9-fold more efficient than those supratidal soils. Moreover, incubation of under tidal fluctuations dramatically by 4.3-fold. The hydrology triggered alternation between biotic reduction and abiotic oxidation could accelerate the reactive ferrous ions amorphous ferric oxyhydroxides, making into metastable phases (RAMPs) with reduced crystallinity promoting surface electrochemical activities. Those RAMPs displayed activity Investigations nationwide coastal verified ubiquitously Our study demonstrates effective formation hydrological perturbations, which provides insights natural sources.

Language: Английский

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Arsenic Contamination of Groundwater Is Determined by Complex Interactions between Various Chemical and Biological Processes

Toxics, Journal Year: 2024, Volume and Issue: 12(1), P. 89 - 89

Published: Jan. 19, 2024

At a great many locations worldwide, the safety of drinking water is not assured due to pollution with arsenic. Arsenic toxicity matter both systems chemistry and biology: it determined by complex intertwined networks chemical reactions in inanimate environment, microbes that human body. We here review what known about these their interconnections. then discuss how consideration aspects arsenic levels groundwater may open up new avenues towards realization safer water. Along such avenues, geochemical microbiological conditions can optimize microbial ecology vis-à-vis reduced toxicity.

Language: Английский

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New Insights into the Controversy of Reactive Mineral-controlled Arsenopyrite Dissolution and Arsenic Release

Water Research, Journal Year: 2024, Volume and Issue: 262, P. 122051 - 122051

Published: July 5, 2024

Language: Английский

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A Critical Look at Colloid Generation, Stability, and Transport in Redox-Dynamic Environments: Challenges and Perspectives

ACS Earth and Space Chemistry, Journal Year: 2024, Volume and Issue: 8(4), P. 630 - 653

Published: March 22, 2024

Colloid generation, stability, and transport are important processes that can significantly influence the fate of nutrients contaminants in environmental systems. Here, we critically review existing literature on colloids redox-dynamic environments summarize current state knowledge regarding mechanisms colloid generation chemical controls over colloidal behavior such environments. We also identify critical gaps, as lack universally accepted cross-discipline definition modeling infrastructure hamper an in-depth understanding behavior, potential. propose to go beyond a size-based operational consider functional differences between dissolved species. argue predict environments, more empirical data needed parametrize validate models. components element budgets systems must urgently be considered field well lab experiments reactive intend bring further clarity openness reporting measurements improve consistency. Additionally, suggest methodological toolbox for examining impacts redox dynamics experiments.

Language: Английский

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Simultaneous removal of Cr(VI), As(III), and sulfanilamide via an e-barrier electrochemical system: A pilot study

Journal of Hazardous Materials, Journal Year: 2025, Volume and Issue: 490, P. 137735 - 137735

Published: Feb. 27, 2025

Language: Английский

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Transport and Surface Complexation in Subsurface Flow-through Systems

Reviews in Mineralogy and Geochemistry, Journal Year: 2025, Volume and Issue: 91A(1), P. 353 - 381

Published: March 28, 2025

Language: Английский

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Aerobic respiration controls on shale weathering

Geochimica et Cosmochimica Acta, Journal Year: 2022, Volume and Issue: 340, P. 172 - 188

Published: Nov. 8, 2022

The weathering of shale exerts an important control on the hydrochemical fluxes to river systems, thus influencing global carbon, nutrient, and geochemical cycles. However, quantitative understanding its impact biogeochemical cycles remains inadequate due complex interplay between hydrological, biogeochemical, physical processes. In this study, we develop a novel modeling approach quantitatively interpret long-term chemical occurring since last glaciation period (15,000 years) leading present conditions. model explicitly considers processes across multiple phases involved in weathering, including: (i) infiltration meteoric water, (ii) interactions water mineral assemblage via dissolution/precipitation reactions, (iii) microbially-mediated oxidation organic matter, (iv) evolution porosity induced by (v) exchange gases subsurface atmosphere. To implement test our model, conduct study at well-instrumented hillslope underlain Mancos Shale located East River site, Western Colorado. Consistent with field observations, successfully reproduces stratified front, spatial distribution gaseous emissions carbon dioxide from subsurface. Model simulations show that aerobic respiration fundamental shale. While previous studies have highlighted diffusion oxygen atmosphere as primary mechanism for demonstrate limits propagation shallow subsurface, thereby inhibits dissolution pyrite depth. Aerobic is particularly favored top soil horizon constant flux atmosphere, replenishment fresh litter/plant-derived lesser extent presence fossil shale-associated matter. acidic pore generated through within transported greater depths, where it sustains carbonate (dolomite example). Overall, results depletion fronts are significantly different, primarily depend ability microorganisms carry out microbial various transport pathways reactants controlling reactions under partially saturated

Language: Английский

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Multicomponent and Surface Charge Effects on PFOS Sorption and Transport in Goethite-Coated Porous Media under Variable Hydrochemical Conditions

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(31), P. 13866 - 13878

Published: July 22, 2024

Perfluorooctanesulfonate (PFOS), a toxic anionic perfluorinated surfactant, exhibits variable electrostatic adsorption mechanisms on charge-regulated minerals depending solution hydrochemistry. This work explores the interplay of multicomponent interactions and surface charge effects PFOS to goethite surfaces under flow-through conditions. We conducted series column experiments in saturated goethite-coated porous media subjected dynamic hydrochemical conditions triggered by step changes electrolyte concentration injected solutions. Measurements pH breakthrough curves at outlet allowed tracking propagation reactive fronts. performed process-based transport simulations incorporating mechanistic network complexation reactions quantitatively interpret geochemical processes. The experimental modeling outcomes reveal that coupled spatio-temporal evolution fronts, driven properties mineral, exerts key control mobility determining its speciation surfaces. These results illuminate important influence processes mobility, emphasizing need for models ionizable PFAS compounds determine their environmental fate perform accurate risk assessment.

Language: Английский

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Oxidative Weathering of Neutral Mine Drainage from Gold Mine Tailings Impoundment: Tracking Formation and Transformation of Biogenic Iron Minerals and the Associated Arsenic

ACS Earth and Space Chemistry, Journal Year: 2024, Volume and Issue: 8(2), P. 335 - 347

Published: Jan. 31, 2024

Globally, tailing impoundment failures frequently occur, making safely held hazardous materials mobile. The pore water within the tailings can have (near-) neutral pH due to acid neutralization before disposal, leading generation of mine drainage (NMD) as it leaks from impoundment. biogeochemical evolution key elements, particularly Fe, and associated mobility toxic trace metals, including arsenic (As), in these NMD scenarios remain insufficiently explored. In this study, we investigated oxidative weathering originating a gold Taojiang City, China, where sampled tailings' approached neutrality (pH: 6.82). Our observations revealed distinct helically twisted tubular-like structures biogenic Fe minerals suspended particles water. dominant Fe-oxidizing bacteria were identified belonging Crenothrix genus. Further characterization ferrihydrite (Fh) amorphous ferric arsenate (AFA). During weathering, transformations occurred, converting Fh hematite/goethite AFA scorodite. These transformed accumulated orange-brown precipitates at impoundment's toe. Arsenite underwent complete oxidation As(V) outside Arsenic was immobilized by mineral potential through both surface adsorption structural incorporation mechanisms. Given prevalence mine-impacted areas, findings case study broad indications for similar environmental settings. results not only fill knowledge gaps related cycling but also provide significant guidance control.

Language: Английский

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Marine Microplastics Enhance Release of Arsenic in Coastal Aquifer during Seawater Intrusion Process

Journal of Hazardous Materials, Journal Year: 2024, Volume and Issue: 475, P. 134804 - 134804

Published: June 3, 2024

Language: Английский

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