Remediation of GenX from water by amidoxime surface-functionalized electrospun polyacrylonitrile nanofibrous adsorbent

As a short-chain PFAS, GenX has gained increasing attention in recent years as a hazardous and emerging contaminant in water bodies. However, there is only limited research outcome up to date to address GenX remediation from water. In this research, we investigated amidoxime surface-functionalized PAN nanofibrous material from electrospinning as adsorbent to remove GenX from water. The nanofibrous adsorbent from 10 min treatment of electrospun PAN nanofibrous material in hydroxylamine (ASFPAN10) realized 35% GenX removal from a 100 mg/L aqueous solution at pH = 4 and 0.24 g/L loading after a simple one-time filtration with a GenX removal capacity of ~0.6 mmol/g. The mechanism study indicated that the GenX adsorption on PAN nanofibrous adsorbent could be mainly ascribed to hydrophobic interaction and dipole-dipole interaction between C[tbnd]N and C–F while the GenX adsorption on ASFPAN10 nanofibrous adsorbent could be mainly attributed to coulomb force between positive-charged C[dbnd]N+(OH)–H from ASFPAN10 and negative-charged COO− from GenX. Compared to that of PAN, the more hydrophilic surface of ASFPAN10 facilitated water access to the nanofibrous adsorbent surface and also contributed to the higher GenX removal efficiency. For the first time, this research pointed out a direction to use common economic materials for effective remediation of short-chain PFAS from water bodies especially at relatively high PFAS centration.