Removal of Trace As(V) from Water with the Titanium Dioxide/ACF Composite Electrode

The novel titanium oxide/active carbon fiber (TiO2/ACF) electrode was prepared, and electrosorptive properties for As(V) in aqueous solution were investigated. The structure of TiO2/ACF was characterized with transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). Furthermore, the As(V) electrosorptive properties of TiO2/ACF electrodes with calcination temperature, ionic species, and loaded amount of TiO2 were measured, and the electrosorption isotherm and kinetics were investigated at the applied voltage of 1.5 V. The optimal load quality of TiO2 was 0.80 g per ACF electrode (length × width × height = 2 cm × 1 cm × 0.4 cm, 0.30 g), and optimum calcination temperature was 450 °C. The maximum electrosorption capacity of TiO2/ACF was 8.09 mg/g, about 200 % higher than that of ACF. Moreover, the electrode performance was stable than other materials such as pure ACF, manganese oxide/ACF, and iron oxides/ACF. It can process 100 ppb As(V) of water to 6 ppb (reach the drinking water standards of WHO), demonstrating that our novel electrode is with potential practical application.