Rapid Removal of Poly- and Perfluoroalkyl Substances with Quaternized Wood Pulp

Abstract

Across the United States, many municipalities are utilizing adsorbents to remove pervasive poly- and perfluoroalkyl substances (PFASs) from their drinking water. However, conventional adsorbents usually require long contact times (minutes to days) to achieve high removal efficiencies. To overcome this limitation, we developed materials that rapidly adsorb anionic PFASs from water within seconds. More specifically, we discovered that cellulose fibers functionalized with cationic amines (quaternized wood pulp (QWP)) removed more than 80% of the most prevalent PFASs (perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA)) within seconds at environmentally relevant concentrations (∼2.5 μg/L). In contrast, the QWPs were less efficient at adsorbing shorter chain PFASs (<30%). The maximum adsorption capacity values of the best QWP were found to be 763 and 605 mg/g for PFOS and PFOA, respectively, which are competitive with both conventional and newer adsorbents. This work highlights how functionalized cellulose fibers, which are both bio-sourced and biodegradable, may be a promising material for advancing water treatment technologies.