Cationic polymer for selective removal of GenX and short-chain PFAS from surface waters and wastewaters at ng/L levels

Mohamed Ateia; Md Arifuzzaman; Steven Pellizzeri; Mohamed F Attia; Nishanth Tharayil; Jeffrey N Anker; Tanju Karanfil

doi:10.1016/j.watres.2019.114874

Cationic polymer for selective removal of GenX and short-chain PFAS from surface waters and wastewaters at ng/L levels

Water Res. 2019 Oct 15:163:114874. doi: 10.1016/j.watres.2019.114874. Epub 2019 Jul 15.

Authors

Mohamed Ateia¹, Md Arifuzzaman², Steven Pellizzeri³, Mohamed F Attia², Nishanth Tharayil⁴, Jeffrey N Anker², Tanju Karanfil⁵

Affiliations

¹ Department of Environmental Engineering and Earth Science, Clemson University, Clemson, SC, 29634, USA.
² Department of Chemistry, Clemson University, Clemson, SC, 29634, USA.
³ Department of Chemistry, Clemson University, Clemson, SC, 29634, USA; Department of Chemistry and Biochemistry, Eastern Illinois University, Charleston, IL, USA.
⁴ Department of Plant & Environmental Sciences, Clemson University, Clemson, SC, 29634, USA.
⁵ Department of Environmental Engineering and Earth Science, Clemson University, Clemson, SC, 29634, USA. Electronic address: tkaranf@clemson.edu.

PMID: 31336210
DOI: 10.1016/j.watres.2019.114874

Abstract

The emerging classes of perfluorinated alkyl substances (PFAS) (e.g., Perfluorobutanoic acid (PFBA), perfluorobutane sulfonic acid (PFBS), GenX, ADONA, and F-53B) are persistent and recalcitrant to removal by conventional treatment techniques. Herein, we report on poly (N-[3-(dimethylamino)propyl]acrylamide, methyl chloride quaternary, DMAPAA-Q) hydrogel matrix as an effective sorbent for sequestering PFAS from different water matrices. The selective removal of 16 PFAS from different classes using DMAPAA-Q polymer was confirmed in surface waters and treated wastewater at environmentally relevant concentration (i.e., <1000 ng/L). The results showed fast removal kinetics with equilibrium time of 60-120 min and a higher removal of sulfonated than carboxylic PFAS, regardless of their chain lengths. These observations were in agreement with adsorption energy calculations of short- and long-chain PFAS on poly DMAPAA-Q hydrogel using density functional theory (DFT). No desorption was observed when the experimental time was extended to 24 h, which gives an added advantage of poly DMAPAA-Q hydrogel over previously reported adsorbents in the literature. In addition, the removal efficiency was not affected under a varying pH range of 4-10. The impact of background anions on PFAS removal by poly DMAPAA-Q hydrogel was tested and found to follow an order of SO₄^2- > Cl^- > NO₃^-. The performance of poly DMAPAA-Q hydrogel was maintained in six consecutive adsorption/regeneration cycles to remove PFAS. The unique fast kinetics and high adsorption activity of poly DMAPAA-Q hydrogel towards PFAS exhibits a great potential for being a promising material for PFAS control.

Keywords: Cationic polymer; Density functional theory; GenX; Selective removal; Short-chain PFAS.

MeSH terms

Adsorption
Fluorocarbons*
Polymers
Wastewater
Water Pollutants, Chemical*

Substances

Fluorocarbons
Polymers
Waste Water
Water Pollutants, Chemical