Catalytic wet air oxidation of high BPA concentration over iron-based catalyst supported on orthophosphate.

The catalytic performance of Fe supported on nickel phosphate (NiP) was evaluated for the removal of bisphenol A (BPA) by catalytic wet air oxidation (CWAO) at 140 °C and 25 bar of pure oxygen pressure. The prepared NiP and Fe/NiP materials were fully characterized by XRD, N2-physisorption, H2-TPR, TEM, and ICP analysis. Iron (Fe/NiP) impregnation of NiP support enhanced the BPA removal efficiency from 37.0 to 99.6% when CWAO was performed. This catalyst was highly stable given the operating conditions of acidic medium, high temperature, and high pressure. The Fe/NiP catalyst showed an outstanding catalytic activity for oxidation of BPA, achieving almost complete removal of BPA in 180 min at a concentration of 300 mg/L, using 4 g/L of Fe/NiP. No iron leaching was detected after the CWAO of BPA. The stability of Fe/NiP was performed over three consecutive cycles, noting that BPA conversion was not affected and iron leaching was negligible. Therefore, this catalyst (Fe/NiP) could be considered as an innocuous and effective long-lasting catalyst for the oxidation of harmful organic molecules.