Enhanced adsorption of perfluoro alkyl substances for <i>in situ</i> remediation

Aly, Yousof H.; McInnis, Daniel P.; Lombardo, Samuel M.; Arnold, William A.; Pennell, Kurt D.; Hatton, James W.; Simcik, Matt F.

doi:10.1039/c9ew00426b

Cited by 37 publications

(35 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Testing for the ex situ treatment of PFAS-impacted water using activated carbon and ion-exchange resin (IER) have been studied extensively, However, only limited laboratory testing of reagents for the in situ treatment of PFAS have been conducted. Aly et al (2019) demonstrated that cationic polymers mixed with soil can be effective in attenuating various PFAS in column studies, while Wang and Shih (2011) and Barajas (2019) showed that alumina and biochar can act as adsorbents for PFAS, respectively.…”

Section: Introductionmentioning

confidence: 99%

Six pilot‐scale studies evaluating the in situ treatment of PFAS in groundwater

McGregor¹

2020

Remediation Journal

View full text Add to dashboard Cite

Per‐ and polyfluoroalkyl substances (PFAS) have been identified by many regulatory agencies as emerging contaminants of concern in a variety of media including groundwater. Currently, there are limited technologies available to treat PFAS in groundwater with the most frequently applied approach being extraction (i.e., pump and treat). While this approach can be effective in containing PFAS plumes, previous studies of pump and treat programs have met with limited remedial success. In situ treatment studies of PFAS have been limited to laboratory and a few field studies. Six pilot‐scale field studies were conducted in an unconfined sand aquifer coimpacted by petroleum hydrocarbon along with PFAS to determine if a variety of reagents could be used to attenuate dissolved phase PFAS in the presence of petroleum hydrocarbons. The six reagents consisted of two chemical oxidants, hydrogen peroxide (H2O2) and sodium persulfate (Na2S2O8), and four adsorbents, powdered activated carbon (PAC), colloidal activated carbon (CAC), ion‐exchange resin (IER), and biochar. The reagents were injected using direct push technology in six permeable reactive zone (PRZ) configurations. Groundwater concentrations of various PFAS entering the PRZs ranged up to 24,000 µg/L perfluoropentanoic acid, up to 6,200 µg/L pentafluorobenzoic acid, up to 16,100 µg/L perfluorohexanoic acid, up to 6,080 µg/L perfluoroheptanoic acid, up to 450 µg/L perfluorooctanoic acid, and up to 140 µg/L perfluorononanoic acid. Performance groundwater sampling within and downgradient of the PRZs occurred for up to 18 months using single and multilevel monitoring wells. Results of groundwater sampling indicated that the PFAS were not treated by either the persulfate nor the peroxide and, in some cases, the PFAS increased in concentration immediately following the injection of peroxide and persulfate. Concentrations of PFAS in groundwater sampled within the PAC, CAC, IER, and biochar PRZs immediately after the injection were determined to be less than the method detection limits. Analyses of groundwater samples over the 18‐month monitoring period, indicated that all the PRZs exhibited partial or complete breakthrough of the PFAS over the 18‐month monitoring period, except for the CAC PRZ which showed no PFAS breakthrough. Analysis of cores for the CAC, PAC, and biochar PRZs suggested that the CAC was uniformly distributed within the target injection zone, whereas the PAC and biochar showed preferential injection into a thin coarse‐sand seam. Similarly, analysis of the sand packs of monitoring wells installed before the injection of the CAC, PAC, and biochar indicated that the sand packs of the PAC and biochar preferentially accumulated the reagents compared with the reagent concentrations within the surrounding aquifer by up to 18 times.

show abstract

Section: Introductionmentioning

confidence: 99%

Six pilot‐scale studies evaluating the in situ treatment of PFAS in groundwater

McGregor¹

2020

Remediation Journal

View full text Add to dashboard Cite

show abstract

“…The mobilizing amendments help to desorb PFAS compounds that are bound to soil minerals or organic matter, and hence increase their bioavailability and mobility (Milinovic et al, 2015(Milinovic et al, , 2016Pan et al, 2009;Tang et al, 2017). In contrast, the immobilizing amendments adsorb or fix the PFAS compounds in soils reducing their bioavailability and mobility (Aly et al, 2019;Das et al, 2013;Hale et al, 2017). This review discusses all the above strategies by first presenting an overview of various soil PFAS sources, PFAS interactions with soil components and bioavailability, soil PFAS remediation through manipulating the bioavailability using conventional and advanced soil amendments along with some exemplary case studies, and highlighting their respective techno-economic advantages and disadvantages.…”

Section: Supplementary (Si) Figuresmentioning

confidence: 99%

“…Some liquid-based amendments were also used to facilitate PFAS immobilisation in contaminated solid media. For example,Aly et al (2019) observed a six-fold increase of PFAS retention in contaminated soils by applying a commercially available coagulant. Similarly,Pan et al (2009) calculated the thermodynamic index of irreversibility (TII) for PFOS to sediments in the presence of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), to quantify the degree of sorption irreversibility caused by CTAB, with a value of 0 representing a highly reversible system and 1 representing irreversible sorption.…”

mentioning

confidence: 99%

Remediation of poly- and perfluoroalkyl substances (PFAS) contaminated soils – To mobilize or to immobilize or to degrade?

Bolan¹,

Sarkar

Yan

et al. 2021

Journal of Hazardous Materials

206

View full text Add to dashboard Cite

show abstract

“…The most applied technologies for the treatment of PFAS in water treated above ground are systems utilize activated carbon and ion‐exchange resin. Limited laboratory and field studies have been conducted looking at the possibility of using in situ methods to address PFAS‐impacted groundwater (Aly et al, 2019; Barajas, 2019; Bruton & Sedlak, 2017; Carey & McGregor, 2019; Dombrowski et al, 2018; Eberle et al, 2017; Liu et al, 2020; McGregor, 2018; McGregor, 2020; Park et al, 2016). The use of in situ methods for the treatment of PFAS offers several advantages over extraction technologies including lower costs and flexibility.…”

Section: Introductionmentioning

confidence: 99%

The in situ treatment of TCE and PFAS in groundwater within a silty sand aquifer

McGregor¹,

Zhao²

2021

Remediation Journal

View full text Add to dashboard Cite

Chlorinated ethenes such as trichloroethene (TCE), cis-1,2-dichloroethene (cis-1,2-DCE), and vinyl chloride along with per-and polyfluoroalkyl substances (PFAS) have been identified as chemicals of concern in groundwater; with many of the compounds being confirmed as being carcinogens or suspected carcinogens. While there are a variety of demonstrated in-situ technologies for the treatment of chlorinated ethenes, there are limited technologies available to treat PFAS in groundwater. At a former industrial site shallow groundwater was impacted with TCE, cis-1,2-DCE, and vinyl chloride at concentrations up to 985, 258, and 54 µg/L, respectively. The groundwater also contained maximum concentrations of the following PFAS: 12,800 ng/L of perfluoropentanoic acid, 3,240 ng/L of perfluorohexanoic acid, 795 ng/L of perfluorobutanoic acid, 950 ng/L of perfluorooctanoic acid, and 2,140 ng/L of perfluorooctanesulfonic acid. Using a combination of adsorption, biotic, and abiotic degradation in situ remedial approaches, the chemicals of concern were targeted for removal from the groundwater with adsorption being utilized for PFAS whereas adsorption, chemical reduction, and anaerobic biodegradation were used for the chlorinated ethenes. Sampling of the groundwater over a 24-month period indicated that the detected PFAS were treated to either their detection, or below the analytical detection limit over the monitoring period. Postinjection results for TCE, cis-1,2-DCE, and vinyl chloride indicated that the concentrations of the three compounds decreased by an order of magnitude within 4 months of injection, with TCE decreasing to below the analytical detection limit over the 24-month monitoring period. Cis-1, 2-DCE, and vinyl chloride concentrations decreased by over 99% within 8 months of injections, remaining at or below these concentrations during the 24-month monitoring period. Analyses of Dehalococcoides, ethene, and acetylene over time suggest that microbiological and reductive dechlorination were occurring in conjunction with adsorption to attenuate the chlorinated ethenes and PFAS within the aquifer. Analysis of soil cores collected pre-and post-injection, indicated that the distribution of the colloidal activated carbon was influenced by small scale heterogeneities within the aquifer. However, all aquifer samples collected within the targeted injection zone contained total organic carbon at concentrations at least one order of magnitude greater than the preinjection total organic carbon concentrations.

show abstract

Enhanced adsorption of perfluoro alkyl substances for in situ remediation

Abstract: Numerous groundwater sites around the globe have been contaminated by aqueous film forming foam (AFFF) as a result of firefighting, fire training activities and the storage and accidental spillage of AFFF.

Cited by 37 publications

References 26 publications

Six pilot‐scale studies evaluating the in situ treatment of PFAS in groundwater

Six pilot‐scale studies evaluating the in situ treatment of PFAS in groundwater

Remediation of poly- and perfluoroalkyl substances (PFAS) contaminated soils – To mobilize or to immobilize or to degrade?

The in situ treatment of TCE and PFAS in groundwater within a silty sand aquifer

Contact Info

Product

Resources

About