Abatement of 1,1,2,2-tetrachloroethane in water by reduction at silver cathode and oxidation at boron doped diamond anode in micro reactors

The treatment of aqueous solutions of 1,1,2,2-tetrachloroethane was performed by anodic oxidation at boron doped diamond (BDD), cathodic reduction at silver and coupled processes. Experiments were performed in macro and micro reactors with an interelectrode distance lower than 100 μm. Drastically higher abatements of the chlorinated compound and current efficiencies were obtained in microdevices that, furthermore, allowed to perform the electrolyses with low cell voltages in the absence of supporting electrolyte. When reduction and oxidation processes were carried out simultaneously in the microreactor, a higher abatement of pollutants was obtained with the same amount of the passed charge and applied cell voltage with respect to uncoupled processes. The effect of some operative parameters, including the flow rate, the current density, the initial concentration of the pollutant and the interelectrodic distance, on the performances of the process was also studied.

► Very high abatements of chlorinated compound are achieved in micro electrochemical reactors.
► Comparison between reduction, oxidation and combined processes was carried out.
► Development of an efficacy electrochemical way to treat aliphatic chlorinated hydrocarbons based on coupled processes and microreactors.