Electrochemical Oxidation of Ce(III) to Ce(IV) in Mixed Acid (H2SO4 and CH3SO3H)
Electrochemical behaviors of Ce3+/Ce4+ couple in mixed acid (H2SO4 and CH3SO3H) were investigated on Pt electrode. Polarization curves and electrochemical impedance spectroscopy (EIS) were used to optimize mixed acid composition, and the mixed acid consisting of 1.0 M methanesulfonic acid (MSA) and 0.8 M sulfuric acid is singled out as the optimum electrolyte. Subsequently, the effects of current density and electrolyte temperature on the electrochemical oxidation of Ce3+ to Ce4+ were researched. A 92.2% current efficiency was achieved at 40 mA•cm-2 in cerium (III) solution with the optimum mixed acid electrolyte above at 313 K. It can satisfy the application of mediated electrochemical oxidation process with Ce3+/Ce4+ mediator.
H. L. Zhao et al., "Electrochemical Oxidation of Ce(III) to Ce(IV) in Mixed Acid (H2SO4 and CH3SO3H)", Advanced Materials Research, Vols. 588-589, pp. 90-94, 2012