Simultaneous degradation of p-arsanilic acid and inorganic arsenic removal using M-rGO/PS Fenton-like system under neutral conditions.

In this study, magnetic material based reduced graphene oxide (M-rGO) was prepared through co-precipitation and displayed high catalytic efficiency together with persulfate (PS) for simultaneous p-arsanilic acid (p-ASA) decomposition and arsenic removal. Linear sweep voltammetry and chronoamperometric measurements with M-rGO revealed that PS was effectively bound to M-rGO surface and probably formed charge transfer complex, in which M-rGO was pivotal in mediating facile electron transfer. The effects of pH, temperatures, anions, p-ASA concentration, PS, and M-rGO dosages on p-ASA decomposition were studied in the system. Excellent degradation of p-ASA was carried out at a wide range of pH values, which was unattainable by other Fenton-like processes. Under optimal conditions, M-rGO exhibited prominent removal of both p-ASA (98.8 %) and inorganic arsenic (89.8 %). M-rGO had reasonably excellent repeatability and stability, and 77.7 % p-ASA degraded in the third recovered catalyst. The advantages of environmental friendliness, short reaction time, and straightforward synthesis of M-rGO will facilitate the development of heterogeneous Fenton-like catalysts under neutral conditions.