Analysis of the Use of Copper Electrode in a Filter-Press Electrochemical Reactor for the Electrochemical Reduction of Cr(VI)

摘要

In this work, the Cr(VI) electrochemical reduction by Cyclic Voltammetry (CV) and Linear Sweep Voltammetry (LSV), in acidic solutions and on a copper electrode, was studied. Cr(VI) reduction occurs in one step by a diffusive process at -230 mV /Ag/AgCl. The results obtained by LSV suggest a mass-transfer control for Cr(VI) reduction. The diffusion coefficient obtained for Cr(VI) was D{sub}(HCrO{sub}4){sup}-=1.1×10{sup}(-5)cm{sup}2s{sup}(-1). The polarization curves obtained in a Filter-Press Electrochemical Reactor (FPER) corroborate the mechanism obtained with smaller electrodes and this allowed determining the best electrolysis voltage (2.0V). The electrolysis showed conversions up to 70% in 60 min for solutions with 110ppm of Cr(VI) in batch recycle mode.