Removal of diazinon from aqueous solutions using alternating current in a three-dimensional electrochemical system containing MC/Fe3O4 nanocomposites

Abstract

This study aims to determine diazinon removal using a three-dimensional electrochemical system supplied with alternating current (AC), which uses Fe3O4 magnetite nanoparticles immobilized on microbial cellulose (MC). The nanocomposites are used as catalysts to activate persulfate and produce sulfate radicals for diazinon removal. The surface properties and morphology of MC/Fe3O4 nanocomposites were determined by Fourier Transform Infrared Spectroscopy (FT-IR), Field Emission Scanning Electron Microscopes (FE-SEM), Thermo-Gravimetric Analysis (TGA), and X-Ray Diffraction (XRD) techniques. The studied variables were initial pH (3–9), diazinon concentration (10–40 mg/l), persulfate concentration (0.5–0.8 mmol/l), Na2SO4 concentration (0.1–0.7), MC/Fe3O4 nanocomposite concentration (01–0.3 g/l), voltage (1–7 V), and time (0−60). The obtained results indicated that the 3D electrochemical system could lead to complete removal in the presence of the MC/Fe3O4 catalyst in optimal conditions (10 mg/l initial diazinon concentration, 0.5 g/l Na2SO4, pH of 3 ± 0.5, 0.7 mmol/l PS, 0.25 g/l MC/Fe3O4, and 5 V AC) during 60 min. The energy consumption in this system was calculated 0.35 KW h/m3. The role of each process involved in diazinon removal and the reaction kinetics were also provided in this study.