Abstract:Aluminum modified activated carbon fiber electrode (ACF-Al) was prepared by sol-gel method applying activated carbon fiber and aluminum isopropoxide as raw materials. Electro-adsorption performance of Cr(Ⅵ) in simulated wastewater was studied by single factor and orthogonal experiments. Electrode materials were characterized by XRD, FTIR and SEM. After adsorption equilibrium was achieved, electrode was regenerated. The experimental results show that Cr(Ⅵ) adsorption rate is close to 100%, which is 26.25 point percent higher than that under open circuit condition, and suitable process conditions including initial concentration of simulated wastewater of 40 mg/L, pH value of 2.5, electrode potential of 0.3 V, polar plate spacing of 6 mm, and ACF-Al plate area of 100 cm2. Electro-adsorption process fits well with Langmuir adsorption isotherm model and can be well described by Quasi-second-order kinetics equation. After four cycles of regeneration process on activated carbon fiber electrode, adsorption and removal rate of Cr(Ⅵ) remains 87% above. Characterization results show that activated alumina is successfully loaded on surface of activated carbon fiber, which improves its conductivity, enhances directional migration of Cr(Ⅵ) to the plate, and removes Cr(Ⅵ) effectively under action of carboxyl and hydroxyl groups on surface.