Electro-enhanced adsorption of As(V) by activated carbon in three-dimensional electrode reactor
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Central South University, Changsha 410083, China;
3. School of Environment and Safety Engineering, North University of China, Taiyuan 030051, China)
2. Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution, Central South University, Changsha 410083, China;
3. School of Environment and Safety Engineering, North University of China, Taiyuan 030051, China)
Abstract: This study focused on As(V) removal by electrosorption in a self-made three-dimensional electrode reactor, in which granular activated carbon (GAC) was used as the particle electrode. Under the optimal conditions, the removal efficiency of As(V) was 84%, and its residual concentration in solution was 0.08 mg/L. From kinetic investigation, the rate determining steps of the entire process may involve more than two processes: membrane diffusion, material diffusion and physical/chemical adsorption processes. During the desorption process, As(V) can be desorbed from GAC, and the GAC was able to electro-adsorb As(V) again after desorption, which means that the electrode has good cycling performance.
Key words: arsenic removal; activated carbon; electrosorption; three-dimensional electrode reactor