KINETICS OF BROMINE-TRIBROMIDE-BROMIDE REDOX PROCESSES ON PLATINUM ELECTRODES IN ACETONITRILE SOLUTIONS

The electrochemistry of solutions of lithium bromide and bromine in acetonitrile has been investigated in the temperature range from 0 to 30°C, using a platinum rotating disk working electrode from 200 to 2000 rpm. Both the anodic and cathodic current/voltage curves are characterized by two well-defined waves From the diffusion-controlled processes, the diffusion coefficients of the defusing species have been evaluated. The current/voltage curves in a region before the limiting current have an appreciable degree of irreversibility. The kinetic parameters were obtained by the Frumkin-Tedoradse method for intermediate kinetics and it is shown that the processes formally fit the type of reaction mechanisms already postulated for the iodine-tri-iodide-iodide system in dimethylsulphoxide and acetonitrile. © 1969.