Treatment of aqueous per- and poly-fluoroalkyl substances: A review of biochar adsorbent preparation methods

Chemosphere, Год журнала: 2024, Номер 357, С. 142088 - 142088

Опубликована: Апрель 20, 2024

Per- and poly-fluoroalkyl substances (PFAS) are synthetic chemicals widely used in everyday products, causing elevated concentrations drinking water posing a global challenge. While adsorption methods commonly employed for PFAS removal, the substantial cost environmental footprint of commercial adsorbents highlight need more cost-effective alternatives. Additionally, existing exhibit limited effectiveness, particularly against diverse types, such as short-chain PFAS, necessitating modifications to enhance capacity. Biochar can be considered eco-friendly alternative conventional adsorbents. With abundant feedstocks favorable physicochemical properties, biochar shows significant potential applied an adsorbent removing contaminants from water. Despite its effectiveness adsorbing different inorganic organic environments, some factors restrict effective application adsorption. These related characteristics well chemistry. Therefore, have been introduced overcome these limitations improve biochar's This review explores preparation conditions, including pyrolysis process, activation, modification techniques capacity types PFAS. It addresses critical questions about performance composites, mechanisms governing adsorption, challenges, future perspectives this field. The surge research on indicates growing interest, making timely valuable resource in-depth exploration remediation.

Язык: Английский

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Comparative Assessment of Powdered versus Granular Activated Carbon for PFAS Removal in Drinking Water Treatment Plants

ACS ES&T Water, Год журнала: 2025, Номер unknown

Опубликована: Янв. 16, 2025

Since the acceptable PFAS levels in drinking water vary among regulatory agencies, treatment plants (DWTPs) are urged to adapt their processes improve removal. This study's objective was assess performance of powdered and granular activated carbon (PAC GAC) for removal evaluate applications DWTPs. Raw filtered waters were used examine different types PAC GAC batch rapid small-scale column tests, respectively. A conventional dose (10 mg/L) eliminated 40% total PFAS76 25% long-chain after 10 min. It would, however, transfer 24 ppb daily biosolids. comparable (equivalent 27,000 BV) removed 43% 80% PFAS. Considering a medium-sized DWTP with target 80%, pretreatment would require an elevated AC 29 mg/L. will incur equivalent cost post-treatment six columns, while remarkably increasing mass dry sludge by 46%. Hence, emerges as better suited instant intervention mitigate contaminations without revoking need long-term solution.

Язык: Английский

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A review of drinking water quality issues in remote and indigenous communities in rich nations with special emphasis on Australia

The Science of The Total Environment, Год журнала: 2023, Номер 903, С. 166559 - 166559

Опубликована: Авг. 24, 2023

This review paper examines the drinking water quality issues in remote and Indigenous communities, with a specific emphasis on Australia. Access to clean safe is vital for well-being of communities worldwide, yet numerous challenges hinder their ability obtain maintain security. focuses water-related faced by populations countries such as United States, Canada, New Zealand, In Australian context, encounter complex related quality, including microbial chemical contamination, exacerbated climate change effects. Analysis trends Queensland, South Wales, Western Australia, Northern Territory reveals concerns regarding various pollutants very high concentrations source leading levels exceeding recommended limits hardness, turbidity, fluoride, iron, manganese after limited treatment facilities available these communities. Inadequate quantity contribute adverse health effects, particularly among who may resort sugary beverages. Addressing requires comprehensive approaches encompassing testing, funding, governance, appropriate sustainable technologies, cultural considerations. Collaborative efforts, risk-based approaches, improved infrastructure are essential ensure equitable access ultimately improving outcomes promoting social equity.

Язык: Английский

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Stability and Biotransformation of 6:2 Fluorotelomer Sulfonic Acid, Sulfonamide Amine Oxide, and Sulfonamide Alkylbetaine in Aerobic Sludge

Environmental Science & Technology, Год журнала: 2024, Номер 58(5), С. 2446 - 2457

Опубликована: Янв. 5, 2024

The 6:2 fluorotelomer sulfonamide (6:2 FTSAm)-based compounds signify a prominent group of per- and polyfluoroalkyl substances (PFAS) widely used in contemporary aqueous film-forming foam (AFFF) formulations. Despite their widespread presence, the biotransformation behavior these wastewater treatment plants remains uncertain. This study investigated FTSAm-based amine oxide FTNO), alkylbetaine FTAB), sulfonic acid FTSA) aerobic sludge over 100-day incubation period. alkylamine FTAA), primary intermediate product FTNO, was indirectly assessed. Their stability ranked based on estimated half-lives (t1/2): FTAB (no obvious products were detected) ≫ FTSA (t1/2 ≈28.8 days) > FTAA ≈11.5 FTNO ≈1.2 days). Seven transformation 15 identified through nontarget suspect screening using high-resolution mass spectrometry. pathways proposed. Interestingly, FTSAm hardly hydrolyzed to further biotransformed perfluoroalkyl carboxylic acids (PFCAs). Furthermore, novel for generation perfluoroheptanoic (PFHpA) from revealed.

Язык: Английский

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Removal of PFOA from water by activated carbon adsorption: Influence of pore structure

Journal of environmental chemical engineering, Год журнала: 2024, Номер 12(5), С. 113923 - 113923

Опубликована: Авг. 23, 2024

Язык: Английский

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Fast analysis of short-chain and ultra-short-chain fluorinated organics in water by on-line extraction coupled to HPLC-HRMS

The Science of The Total Environment, Год журнала: 2024, Номер 943, С. 173682 - 173682

Опубликована: Май 31, 2024

A rapid on-line solid-phase extraction liquid chromatography high-resolution mass spectrometry (on-line SPE-LC-HRMS) method was developed to analyze 11 ultra-short and short-chain PFAS in surface water. Analytical optimization involved screening 7 chromatographic columns 5 SPE columns, as well evaluating loading conditions, filters, sample acidification, mobile phases, phases. The optimized then applied 44 river water samples collected Eastern Canada, including sites near airports with fire-training areas. Among the targeted PFAS, most frequently detected were trifluoroacetic acid (TFA, 4.6-220 ng/L), perfluorobutanoic (PFBA, 0.85-33 perfluoropentanoic (PFPeA, 1.2-2100 trifluoromethane sulfonic (TMS, 0.01-4.3 perfluorobutane (PFBS, 0.07-450 ng/L). Levels of C3-C5 perfluoroalkyl carboxylic acids (PFCAs), C2-C4 sulfonates (PFSAs) n:3 polyfluoroalkyl (n = 2,3; acids) significantly higher bodies area compared rivers urban In contrast, TFA, TMS, 1:3 not elevated, likely reflecting atmospheric deposition or other diffuse sources for these compounds. Nontarget suspect analysis revealed an abundance AFFF-impacted bodies. Perfluoroalkyl sulfonamides (FASA, C2, C3, C5), sulfonamide propanoic (FASA-PrA, C1-C2) 1, 4, 5) first time environmental waters.

Язык: Английский

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PFAS contamination in tap water: Target and suspect screening of zwitterionic, cationic, and anionic species across Canada and beyond

Environment International, Год журнала: 2025, Номер 195, С. 109250 - 109250

Опубликована: Янв. 1, 2025

This study investigated the occurrence of perfluoroalkyl and polyfluoroalkyl substances (PFAS), including anionic, cationic, zwitterionic compounds, in drinking water. Between 2021-2023, an expanded list 76 target PFAS was screened tap water samples mainly from Canada, but also Eastern United States, Mexico, South America (Argentina), Caribbean (Dominican Republic, Cuba), Africa (Algeria, Cameroon, Central African Morocco, Rwanda, Tunisia), Europe (France, Greece, Italy, Spain, Kingdom) Asia (Japan, Vietnam, Iran, Türkiye). An additional ∼ 200 suspect-target were using high-resolution Orbitrap mass spectrometry. The results revealed widespread contamination most frequent perfluorobutane sulfonate (PFBS), perfluorooctane (PFOS), perfluorobutanoic acid (PFBA) with detection rates ≥ 79 %. Several not currently included EPA methods for region-specific trends. For instance, emerging 6:2 fluorotelomer sulfonamidopropyl betaine (6:2 FTAB) found at highest levels cities France, British Columbia (Canada), UK. FTAB likely reflects shifts PFOS-based aqueous film-forming foams (AFFF) past decades, possibly other uses. Short-chain sulfonamides (FBSA, FHxSA) globally recurrent. Bistriflimide, a counterion often used composition ionic liquids production lithium-ion batteries, detected 46 % samples. total linked to fluorochemical industries (surface water), AFFF use (groundwater), landfills (groundwater). database 275 x 153 provides valuable insights toward refining lists relevant be monitored

Язык: Английский

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Emerging Per- and Polyfluoroalkyl Substances in Tap Water from the American Healthy Homes Survey II

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

Опубликована: Янв. 29, 2025

Humans experience widespread exposure to anthropogenic per- and polyfluoroalkyl substances (PFAS) through various media, which can lead a wide range of negative health impacts. Tap water is an important source in communities with any degree contamination but routine or large-scale PFAS monitoring often depends on targeted analytical methods limited measuring specific PFAS. We analyzed 680 tap samples from the American Healthy Homes Survey II for using non-targeted analysis (NTA) expand detectable Based detection frequency relative abundance, about half identified were found only by NTA. (with varying degrees confidence) 75 distinct PFAS, including 57 exclusively detected The are members seven structural subclasses differentiated their head groups fluorination. Clustering categorized into four coabundance dominated subclasses. One group uniquely NTA contains zwitterionic other transformation products likely associated aqueous firefighting foam contaminants small number spatially correlated samples. These results help further characterize scope emerging experienced U.S. population via augment nationwide targeted-PFAS programs.

Язык: Английский

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Target and Suspect Screening Reveal PFAS Exceeding European Union Guideline in Various Water Sources South of Lyon, France

Environmental Science & Technology Letters, Год журнала: 2025, Номер 12(3), С. 327 - 333

Опубликована: Фев. 7, 2025

Lyon, a major hub for chemical industries in France, has been identified as contamination hotspot of per- and polyfluoroalkyl substances (PFAS). Major companies the Pierre-Bénite area have used PFAS production fluoropolymers fluorotelomers, with effluents discharged into Rhône River. This together other sources, such firefighting foam use at vicinal harbor oil depot, likely resulted complex signature. study investigated various water sources southern including ponds, rivers, factory channels, wells, springs, tap water. Out 47 samples, 22 had Σ77PFAS above 100 ng/L (maximum: ∼700 ng/L), 67% samples exceeded European guideline Σ20PFAS. Target profiles were dominated by perfluoroalkyl carboxylates (particularly C4 to C8), agreement their historical or current industrial usage. Suspect screening also revealed occurrence electrochemical fluorination precursors N-sulfopropyldimethylammoniopropyl perfluorohexanesulfonamido acetic acid (N-SPAmP-FHxSAA) bistriflimide (used composition ionic liquids). Certain ESI+ (e.g., 6:2 fluorotelomer sulfonamidopropyl betaine (6:2 FTAB)) ESI- FTS, FTSAS-sulfone) compounds, more prevalent surface than groundwater.

Язык: Английский

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Deeper Defluorination and Mineralization of a Novel PFECA (C7 HFPO-TA) in Vacuum UV/Sulfite: Unique Mechanism of H/OCF₃ Exchange

Environmental Science & Technology, Год журнала: 2023, Номер 57(40), С. 15288 - 15297

Опубликована: Сен. 25, 2023

C7 HFPO-TA is a newly identified alternative to PFOA, which possesses unique structure fragment (CF3O-CF(CF3)-). In this study, we evaluated the chemical reactivity of in advanced oxidation and reduction processes for first time, revealed series unexpected transformation mechanisms. The results showed that reductive degradation based on hydrated electrons (eaq-) was more feasible HFPO-TA. For oxidative degradation, branched -CF3 at α-position carbon posed as spatial hindrance, shielding attack SO4•- -COO-. synergistic effects HO•/eaq- direct photolysis led deeper defluorination mineralization vacuum UV/sulfite (VUV/SF) process. We H/OCF3 exchange converted CF3O-CF(CF3)- into H-CF(CF3)- directly, SO3•- involved mechanism time. connected same next CF3O- group affected C-O bond cleavage site, preferring pathway. compared with PFOA three PFECAs VUV/SF process, highly dependent structures. Degradation kinetics, theoretical calculations, products' analysis provided an in-depth perspective mechanisms pathways

Язык: Английский

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