FeCu-coal gangue heterogeneous activation of peracetic acid for degradation of sulfamethoxazole

A novel FeCu anchored coal gangue (FeCu-CG) composite was prepared by a two-step (acidation and subsequent chemical reduction) method and applied in catalytic activation of peracetic acid (PAA) for sulfamethoxazole (SMX) removal in water. The BET, XPS, SEM , EDS, and XRD characterization of FeCu-CG indicated that it had a porous structure with the S BET area of 36.38 m² g −1 and nano-FeCu particles were successfully loaded in the CG carrier, which provided electrons and Fe(II) for PAA decomposition through the bimetallic corrosion reaction. The hydroxyl radical (HO • ) was verified to be largely responsible for SMX elimination in FeCu-CG/PAA system. More than 96.4 % of SMX was removed by FeCu-CG/PAA in 40 min at initial pH ranging from 5.0 to 9.0. Increasing FeCu-CG dosage from 0.1 to 1.0 g L −1 could enhance SMX degradation in FeCu-CG/PAA system, but higher dosage inhibited SMX removal owing to the aggregation of FeCu-CG particles. Coexisting dissolved organic matter (DOM), HCO 3 - and Cl - suppressed SMX degradation. The degradation pathways of SMX by FeCu-CG/PAA were proffered including hydroxylation, amino oxidation , bond cleavage and coupling reaction based on five detected degradation products .