The kinetics of oxidation of formaldehyde at a platinum electrode in an acid solution

Article abstract of DOI:10.1246/bcsj.63.507

Three types of the retardation were found for the rate of oxidation of formaldehyde at a platinum electrode in 0.5 mol dm^-3 sulfuric acid. These rate retardations are attributed to the blocking of individual reaction sites by strongly chemisorbed species, the inhibition of the pairing of adjacent sites indispensable for the oxidation of formaldehyde, and the accumulation of oxidation intermediates. The oxidation rate under conditions excluding these rate retardations was independent of the potential in the potential range of about 0.4 - 0.6 V vs. a reversible hydrogen electrode and corresponded to first-order kinetics with respect to the formaldehyde concentrations. These kinetic data are explained in terms of a slow adsorption of formaldehyde molecules.