Applications of TiO2-CeO2/bamboo-biochar particle electrodes to enhanced treatment of phenol wastewater in a three-dimensional electrochemical reactors

Phenolic compounds in wastewater are highly biotoxic and harmful to the environment and human health. Due to the shortcomings of traditional treatment methods, the three-dimensional electrochemical reactors (3DERs) have been widely studied in phenol wastewater treatment due to their high efficiency, simple operation and low chemical addition. Particle electrodes are crucial, and TiO2-modified particle electrodes have been shown to contribute to the oxidation of pollutants. The TiO2-CeO2 modified bamboo biochar particle electrodes (BCPEs) were newly prepared by sol-gel and calcination two-step method, and their surface microscopic morphologies, crystal structures, physical and chemical properties were determined by characterization. Electrochemical experiments showed that the mass transfer rate (nu = 15.47 x 10(-3)) and the electrochemically active surface area (ECSA) of TiO2-CeO2 modified BCPEs were larger than that of TiO2/BC and BCPEs. Optimal electrolysis conditions were obtained by the corresponding surface model: the Ti/Ce molar ratio of 10, current density (j) of 32 mA/cm(2), the initial phenol concentration of 100 mg L-1, and the phenol removal reached 83.02%. After 120 min electrolysis of phenol wastewater with an initial concentration of 100 mg L-1 at j = 30 mA/cm(2) in the 3DERs, the phenol removal reached 81.69%. The experimental results showed that the TO2-CeO2 modified BCPEs realized the efficient treatment of phenol wastewater in the 3DERs. This study provides theoretical and technical support for the application of three-dimensional electrodes to the advanced treatment of phenol wastewater.