title: Electrochemical treatment of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) in groundwater impacted by aqueous film forming foams (AFFFs).
abstract: Laboratory experiments were performed to evaluate the use of electrochemical treatment for the decomposition of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), as well as other perfluoroalkyl acids (PFAAs), in aqueous film forming foam (AFFF)-impacted groundwater collected from a former firefighter training area and PFAA-spiked synthetic groundwater. Using a commercially-produced Ti/RuO2 anode in a divided electrochemical cell, PFOA and PFOS decomposition was evaluated as a function of current density (0-20 mA/cm(2)). Decomposition of both PFOA and PFOS increased with increasing current density, although the decomposition of PFOS did not increase as the current density was increased above 2.5 mA/cm(2). At a current density of 10 mA/cm(2), the first-order rate constants, normalized for current density and treatment volume, for electrochemical treatment of both PFOA and PFOS were 46 × 10(-5) and 70 × 10(-5) [(min(-1)) (mA/cm(2))(-1) (L)], respectively. Defluorination was confirmed for both PFOA and PFOS, with 58% and 98% recovery as fluoride, respectively (based upon the mass of PFOA and PFOS degraded). Treatment of other PFAAs present in the groundwater also was observed, with shorter chain PFAAs generally being more recalcitrant. Results highlight the potential for electrochemical treatment of PFAAs, particularly PFOA and PFOS, in AFFF-impacted groundwater.
authors.affiliation: CB&I Federal Services, LLC, 17 Princess Road, Lawrenceville, NJ 08648, USA. Electronic address: schaeferce@cdmsmith.com.
authors.forename: Charles E
authors.initials: CE
authors.lastname: Schaefer
authors.affiliation: CB&I Federal Services, LLC, 17 Princess Road, Lawrenceville, NJ 08648, USA.
authors.forename: Christina
authors.initials: C
authors.lastname: Andaya
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Cantabria, Av. De Los Castros, s/n, 39005 Santander, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Urtiaga
authors.affiliation: Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO 80401, USA.
authors.forename: Erica R
authors.initials: ER
authors.lastname: McKenzie
authors.affiliation: Department of Civil and Environmental Engineering, Colorado School of Mines, Golden, CO 80401, USA.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Higgins
mesh_terms: D017738:Alkanesulfonic Acids / Q000737:chemistry*; D002210:Caprylates / Q000737:chemistry*; D055664:Electrochemical Techniques; D005466:Fluorocarbons / Q000737:chemistry*; D060587:Groundwater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D017738:Alkanesulfonic Acids; D002210:Caprylates; D005466:Fluorocarbons; D014874:Water Pollutants, Chemical; C023036:perfluorooctanoic acid; C076994:perfluorooctane sulfonic acid
keywords: Electrochemical; PFOA; PFOS; Perfluorinated