In-situ preparation of biochar-loaded particle electrode and its application in the electrochemical degradation of 4-chlorophenol in wastewater

Abstract

In order to effectively degrade 4-chlorophenol in wastewater, a biochar-loaded particle electrode was prepared using an in-situ method. The method employed bagasse as the raw material, KOH as the activator, SnCl4·5H2O, MnCl2·4H2O and SbCl3 as the modifiers. Furthermore, X-ray diffraction, scanning electron microscopy and energy dispersive spectrometer were used to characterize the crystal composition, morphology and elemental compositions of the proposed particle electrode. The electrochemical performance of the proposed particle electrode was analyzed using an electrochemical workstation. A three-dimensional packed-bed electrochemical reactor was constructed using the loaded biomass carbon particle electrodes. The effects of different loaded biomass carbon particle electrodes on the electrochemical degradation of 4-chlorophenol were studied, and the mechanism of electrochemical degradation of 4-chlorophenol was discussed. The results showed that the effect of the supported biomass carbon particle electrode on the degradation of 4-chlorophenol was significantly higher than that of the unsupported biomass carbon particle electrode. Additionally, the electrochemical degradation of 4-chlorophenol was greatly influenced by the biomass carbon particle electrode with different loading and concentration. The removal efficiencies of 4-chlorophenol using the electrochemical treatment under the studied experimental conditions were found in the following descending order: Mn/AC > Sn/AC > Sb/AC. Among them, the biomass carbon particle electrode prepared using 150 g L−1 MnCl2·4H2O showed the best treatment effect for 4-chlorophenol. After electrochemical treatment of 500 mg L−1 of 4-chlorophenol-simulated wastewater for 1 h, the removal efficiency of 4-chlorophenol reached 99.93%.