Flow-Through Porous Electrodes

Experimental limiting current data obtained on two systems of known configuration clarify conditions under which internal mass transfer restrictions control the current distribution and collection efficiency of flow-through porous electrodes. At sufficiently low flow rates, the limiting current is controlled by the rate of reactant supply to the electrode. A theoretical model is developed which includes mass transfer, ohmic, kinetic, and geometric parameters. The model succeeds in predicting limiting current behavior over a wide range of operating conditions. A simple algebraic criterion is suggested for estimating the limiting current and collection effectiveness of flow-through porous electrodes.