Systematic Study on the Removal of Per- and Polyfluoroalkyl Substances from Contaminated Groundwater Using Metal–Organic Frameworks

Environmental Science & Technology, Год журнала: 2021, Номер 55(22), С. 15162 - 15171

Опубликована: Окт. 29, 2021

Harmful per- and polyfluoroalkyl substances (PFAS) are ubiquitously detected in aquatic environments, but their remediation remains challenging. Metal–organic frameworks (MOFs) have been recently identified as an advanced material class for the efficient removal of PFAS, little is known about fundamentals PFAS@MOF adsorption process. To address this knowledge gap, we evaluated performance 3 different MOFs 8 PFAS classes from aqueous film-forming foam-impacted groundwater samples obtained 11 U.S. Air Force installations. Due to pore sizes/shapes identity metal node, NU-1000, UiO-66, ZIF-8 were selected investigate role MOF structures, properties, water matrix on We observed that (i) dominated by electrostatic acid–base interactions anionic non-ionic respectively, (ii) preferred long- over short-chain (iii) strongly dependent nature head group functionality, (iv) compromised presence ionic neutral co-contaminants competing ion-exchange sites binding. With study, elucidate mechanism complex sources guide design more treatment PFAS-contaminated bodies.

Язык: Английский

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Insights into the Crucial Role of Electron and Spin Structures in Heteroatom-Doped Covalent Triazine Frameworks for Removing Organic Micropollutants

Environmental Science & Technology, Год журнала: 2022, Номер 56(10), С. 6699 - 6709

Опубликована: Апрель 27, 2022

The water shortage crisis, characterized by organic micropollutants (OMPs), urgently requires new materials and methods to deal with it. Although heteroatom doping has been developed into an effective method modify carbon nanomaterials for various heterogeneous adsorption catalytic oxidation systems, the active source regulated intrinsic electron spin structures is still obscure. Here, a series of nonmetallic element-doped (such as P, S, Se) covalent triazine frameworks (CTFs) were constructed applied remove pollutants using adsorption-photocatalysis process. external mass transfer model (EMTM) homogeneous surface diffusion (HSDM) employed describe It was found that sulfur-doped CTF (S-CTF-1) showed 25.6-fold increase in saturated capacity (554.7 μmol/g) 169.0-fold surge photocatalytic kinetics (5.07 h-1), respectively, compared pristine CTF-1. A positive correlation between accumulation at site (N1 atom) energy further demonstrated experimental results theoretical calculations. Meanwhile, degradation rates greatly enhanced forming built-in electric field driven polarization. In addition, S-CTF-1 maintained 98.3% removal 2,2',4,4'-tetrahydroxybenzophenone (BP-2) 97.6% regeneration after six-cycle sequencing batch treatment real matrices. This work established relation photocatalysis, paving way design modified control OMPs.

Язык: Английский

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Nothing lasts forever: understanding microbial biodegradation of polyfluorinated compounds and perfluorinated alkyl substances

Microbial Biotechnology, Год журнала: 2021, Номер 15(3), С. 773 - 792

Опубликована: Сен. 27, 2021

Poly- and perfluorinated chemicals, including alkyl substances (PFAS), are pervasive in today's society, with a negative impact on human ecosystem health continually emerging. These chemicals now subject to strict government regulations, leading costly environmental remediation efforts. Commercial polyfluorinated compounds have been called 'forever chemicals' due their strong resistance biological chemical degradation. Environmental cleanup by bioremediation is not considered practical currently. Implementation of will require uncovering understanding the rare microbial successes degrading these compounds. This review discusses underlying reasons why degradation heavily fluorinated rare. Fluorinated chlorinated very different respect chemistry physiology. Moreover, end product biodegradation, fluoride, much more toxic than chloride. It imperative understand limitations, elucidate physiological mechanisms defluorination, order better discover, study, engineer bacteria that can efficiently degrade

Язык: Английский

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A Review on Removal and Destruction of Per- and Polyfluoroalkyl Substances (PFAS) by Novel Membranes

Membranes, Год журнала: 2022, Номер 12(7), С. 662 - 662

Опубликована: Июнь 27, 2022

Per- and Polyfluoroalkyl Substances (PFAS) are anthropogenic chemicals consisting of thousands individual species. PFAS consists a fully or partly fluorinated carbon-fluorine bond, which is hard to break requires high amount energy (536 kJ/mole). Resulting from their unique hydrophobic/oleophobic nature chemical mechanical stability, they highly resistant thermal, chemical, biological degradation. have been used extensively worldwide since the 1940s in various products such as non-stick household items, food-packaging, cosmetics, electronics, firefighting foams. Exposure may lead health issues hormonal imbalances, compromised immune system, cancer, fertility disorders, adverse effects on fetal growth learning ability children. To date, very few novel membrane approaches reported effective removing destroying PFAS. Therefore, this article provides critical review treatment removal by separation systems. We discuss recently techniques for include detailed discussion parameters affecting destruction. Moreover, an estimation cost analysis also included each technology. Additionally, technology still growing, we incorporated several future directions efficient treatment.

Язык: Английский

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A Tunable Porous β-Cyclodextrin Polymer Platform to Understand and Improve Anionic PFAS Removal

ACS Central Science, Год журнала: 2022, Номер 8(5), С. 663 - 669

Опубликована: Май 16, 2022

Cross-linked polymers containing β-cyclodextrin (β-CD) are promising adsorbents with demonstrated removal performances for per- and polyfluoroalkyl substances (PFASs) from contaminated water sources. Despite the performance of some β-CD-based PFAS removal, many these materials not amenable rational improvement or addressing fundamental questions about adsorption mechanisms. These ambiguities arise poorly defined structure cross-linked polymers, especially respect to random substitution patterns cyclodextrins as well side reactions that modify structures cross-linkers. Here, we report a new β-CD polymer platform in which styrene groups covalently attached form discrete monomer is radical polymerization. This was polymerized methacrylate comonomers provide three high specific surface areas isolated yields (all >93%). A copolymerized bearing cationic functional group achieved nearly 100% eight anionic PFASs (initial concentration 1 μg/L each compound) nanopure at an exceedingly low adsorbent loading mg L-1, compared previous cyclodextrin required loadings least order magnitude higher achieve equivalent degree removal. Furthermore, when were studied challenging salt matrix, observed long-chain controlled by complementary interplay hydrophobic electrostatic interactions, whereas short-chain primarily relied on interactions. approach demonstrates great promise anticipate compositions will be tailored using versatility polymerization simultaneously target other classes micropollutants future.

Язык: Английский

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Sequestration of per- and polyfluoroalkyl substances (PFAS) by adsorption: Surfactant and surface aspects

Current Opinion in Colloid & Interface Science, Год журнала: 2022, Номер 58, С. 101571 - 101571

Опубликована: Янв. 31, 2022

Язык: Английский

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Sorptive removal of per- and polyfluoroalkyl substances from aqueous solution: Enhanced sorption, challenges and perspectives

The Science of The Total Environment, Год журнала: 2022, Номер 861, С. 160647 - 160647

Опубликована: Ноя. 29, 2022

Язык: Английский

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A Review on Per- and Polyfluoroalkyl Substances (PFAS) Remediation: Separation Mechanisms and Molecular Interactions

ACS ES&T Water, Год журнала: 2022, Номер 2(12), С. 2258 - 2272

Опубликована: Ноя. 3, 2022

Per- and polyfluoroalkyl substances (PFAS) are a group of manmade chemicals, which persistent in the environment, bioaccumulative, toxic to humans. Various treatment technologies have been used remove PFAS from water, among them adsorption membrane filtration shown greater effectiveness removal. Therefore, main objective this article is provide review on current literature investigating removal by technologies. The specific focus explore separation mechanisms involved existing challenges adsorbents/membranes. This highlights research needs for developing more efficient

Язык: Английский

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Carbon-dot hydrogels as superior carbonaceous adsorbents for removing perfluorooctane sulfonate from water

Chemical Engineering Journal, Год журнала: 2022, Номер 435, С. 135021 - 135021

Опубликована: Фев. 4, 2022

Язык: Английский

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Adsorption Mechanism of Perfluorooctanoate on Cyclodextrin-Based Polymers: Probing the Synergy of Electrostatic and Hydrophobic Interactions with Molecular Dynamics Simulations

ACS Materials Letters, Год журнала: 2022, Номер 4(5), С. 853 - 859

Опубликована: Апрель 4, 2022

Contamination of natural water resources by per- and polyfluorinated alkyl substances (PFAS) has affected millions people around the world emphasized need for development novel effective adsorbent materials. We demonstrate how atomistic molecular dynamics (MD) simulations can be used to provide scale insight into role electrostatic hydrophobic interactions on adsorption perfluorooctanoate (PFOA) surfactant, a prominent longer-chain PFAS, polymer-based network in water. Specifically, ammonium salt been investigated β-cyclodextrin (CD) cross-linked with decafluorobiphenyl linkers as an example absorbent material that already demonstrated efficient PFAS adsorption. Examination pairwise reveals importance dual pronged mechanism involving both interactions. The counterions CD segments facilitates attraction anionic headgroup PFOA while fluorinated additional tail well higher affinity toward comparison hydrocarbons. These competing result primarily outside cavity mostly interacting linkers. using "what if" scenarios are powerful approach infer different PFAS.

Язык: Английский

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