Graphene oxide immobilized binuclear biomimetic catalyst for triclosan degradation in aqueous solution

Abstract

Biomimetic catalysts, Zn(salen), Zn(Phe-TPP), ZnPSC6 and graphene oxide (GO) immobilized ZnPSC6 (ZnPSC6/GO), were fabricated. These biomimetic catalysts were tested for catalytic decomposition of emerging contaminant triclosan (TCS). Catalysts were characterized using Brunauer-Emmett-Teller (BET), X-ray Diffraction (XRD), Fourier Transform infrared (FTIR), and Raman spectra. The reaction processes were studied using HPLC, and the treated solutions were tested based on total carbon content (TCC) analysis and toxicity analysis. The impacts of catalysts on TCS degradation were investigated through testing removal efficiency, total carbon content (TCC) and ecotoxicity. The results showed that ZnPSC6/GO displayed high activity due to salen-porphyrin binuclear active sites and immobilization into GO compared with Zn(salen), Zn(Phe-TPP), and ZnPSC6. Finally, the reaction conditions of TCS oxidation catalyzed by ZnPSC6/GO has been preliminarily discussed. In these conditions, high removal efficiency was observed (96.7%; [ZnPSC6/GO] = 3.0 ppm, [TCS] = 0.02 mmol/L, [H2O2] = 0.60 mmol/L, T = 70 °C, t = 90 min, pH = 8).