Electrochemical study on anolyte for electrosynthesis of chromic anhydride on combination electrode of titanium matrix with multiple-unit metal oxides coating
A new green technology of producing chromic anhydride with an electrochemical synthesis method was studied to solve the pollution problems in the traditional production process of chromic anhydride.The anolyte used was sodium dichromate solution, and the anode used was a self-made combination electrode of titanium matrix with a multiple-unit metal oxides active coating.The electrochemical behavior of sodium dichromate solution on a combination electrode of titanium matrix was studied with cyclic voltammetry as a part of the fundamental researches of this technique.The electrooxidation reaction of 160 cycles indicated that the electrode possessed a very stable electrochemical behavior.The peak currents ip and peak potentials Ep of the oxidation peaks for sodium dichromate solution of different concentrations, i.e., water under the existence of sodium dichromate, were experimentally measured at different temperatures and sweep rates v on the electrode.The equations of peak current ip versus v1/2 and peak potential Ep versus lnv were established, indicating that the electrode reaction was an irreversible diffusion-controlled reaction.The kinetic parameters and activation energy of electrode reaction was calculated, and the effects of temperature on the kinetic parameters and activation energy were preliminarily discussed.