Degradation of perfluorooctanoic acid using zero-valent iron coated by carboxymethyl-β-cyclodextrin polymer

Abstract

Polyfluoroalkyl compounds like PFOA are of concern due to widespread use and toxicological risks. nZVI coated with carboxymethyl-β-cyclodextrin polymer (nFe-CMBCD) showed strong PFOA reduction, reaching 98% and 90% at 0.2 and 2 mg/L in 5 min, and 90% at 500 mg/L in 60 min. Degradation products (acetate, formate, perfluoroheptanoic and perfluorohexanoic acids) suggest chain shortening (C8→C7→C6). CMBCD likely enhances adsorption on nZVI and electron transfer, enabling conversion to less harmful substances. To the best of our knowledge, this is the first report demonstrating the successful PFOA degradation using nZVI coated by a supramolecular compound under standard conditions.