Mass Transport Processes at Porous Electrocatalysts in the Electrogenerative Reactor

Abstract

Mass transport limitations were investigated in the electrolyte, gas phase, and in the pores of platinum and palladium black porous electrocatalysts using the electrogenerative reactor. Limiting currents were identical for both catalysts, depending on a power of the bulk reactant concentration, , where ; can be the electrolyte concentration of hydrogen ions or of dissolved ethylene. Mathematical modeling and comparison with the experimental equation provided information regarding limiting processes. In a matrix cell diffusion limited ionic transport at the ethylene cathode. In free electrolytes, free convection can assist mass transport and improve limiting currents. Gas phase limiting current densities were examined in terms of a model involving limiting radial diffusion of dissolved ethylene with a concentration‐dependent surface area and pore utilization.