A voltammetric determination of the rate constant of a one-way homogeneous chemical reaction in a system of two immiscible liquid phases

It has been shown that a comparison of the heights of cyclic voltammetric peaks obtained for electrode reactions coupled with a chemical reaction (ECE mechanism) permits determination of the rate constant of this homogeneous chemical reaction. A theoretical treatment of the voltammetric data obtained for the case of an irreversible (one-way) chemical reaction provides the homogeneous rate constant from the value of the polarization rate at which the peak heights for the electrode reactions of an unreacted reactant and a product of the chemical reaction are equal. The procedure is demonstrated on the potential-controlled Fenton reaction accomplished by the transfer of di- and trivalent iron compounds across a liquid∣liquid interface.