Preparation of novel kaolin-based particle electrodes for treating methyl orange wastewater

A kaolin-based iron molybdate Fe2(MoO4)3-kaolin-450 (FM-kaolin-450), was successfully prepared through wet chemical process and characterized by scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDXS), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), Fourier transform infrared spectrometry (FT-IR) and X-ray photoelectron spectroscopy (XPS). Acting as particle electrodes, FM-kaolin-450 was applied in electrochemical degradation of methyl orange (MO) in aqueous solution. The effects of initial pH, particle electrodes dosage, initial MO concentration, and current density on chemical oxygen demand (COD) removal efficiency of MO were investigated. The results demonstrated that FM-kaolin-450 shows better catalytic properties and stability in MO electrocatalytic degradation. In order to further test its catalytic performance, some other dyes (Acid Orange II, Eeriochrome Blue Black R, and Methylene Blue) were also studied and the results showed that above 97% decoloration was observed for all tested dyes, indicating that FM-kaolin-450 could act as an efficient particle electrode in color removal in most dye wastewater.