Rapid removal of bromate ion from water streams with an electrolytic flow cell

To control bromate (BrO₃⁻) contamination in the water supply, it is necessary to develop a rapid BrO₃⁻ removal technology without a post-treatment. In this study, rapid removal of BrO₃⁻ from water streams was examined using an electrolytic flow cell. Copper was selected as a working electrode for BrO₃⁻ reduction by cyclic voltammetry. The electrolytic flow cell with a layered copper mesh cathode successfully reduced BrO₃⁻ to Br⁻ at around neutral pH. BrO₃⁻ removal followed the pseudo-first order reaction of BrO₃⁻ concentration, and the reaction rate constant based on common logarithm was evaluated to be 0.00224 s⁻¹. Only 3.6 min of contact time was required to decrease BrO₃⁻ concentration in tap water from 30 to 10 μg/L without pH control. Thus, the electrochemical process is feasible for rapid removal of BrO₃⁻ without post-treatment.