Mass transfer in gas-sparged porous electrodes

The electrochemical limiting current method was used to measure mass transfer coefficients with cocurrent upward gas—liquid flow in packed bed electrodes. Liquid—solid and overall gas—solid coefficients were determined from limiting current data in the presence of inert or reactive gas flows with the use of a plug flow model. The presence of inert gas flow increased mass transfer coefficients over those in single-phase flow by a factor of up to 1.7. As a result of boundary layer penetration by gas bubbles, sparging with reactive gas increased mass transfer rates by a factor of up to 3.5.