Destruction of Aqueous-Phase Carbon Tetrachloride in an Electrochemical Reactor with a Porous Cathode

In this work we investigate the use of a continuous-flow, laboratory-scale electrochemical reactor for the destruction of aqueous-phase carbon tetrachloride (CT). The reactor consists of a porous copper foam cathode and a carbon-cloth anode section located downstream from the cathode. Experimental results show that appreciable conversions of CT can be obtained in the reactor, as long as the electrical conductivity of the liquid exceeds 1 S/m. At lower conductivities, most of the cathode exhibits low reactivity for CT-destruction due to relatively low charge transfer overpotentials. A mathematical model was formulated to predict reactor performance. The model takes into account the CT-reduction reaction and the hydrogen evolution reaction on the cathode surface as well as mass transfer limitations. Using the equilibrium potential for CT reduction as the only adjustable parameter, the model adequately represents experimental data for highly conductive solutions.