Steady-State Polarization at Porous, Flow-Through Electrodes with Small Pore Diameter II. Irreversible Kinetics for One-Electron and Consecutive Two-Electron Transfer Reactions

In this paper a model is proposed for the performance of a porous flow-through electrode working on a redox couple, for one-dimensional systems with line pores. The model includes the comoined effects of mass transfer by forced convection and axial dinusion, ohmic potential drop in the pore electrolyte, and activation polarization, on the over-all current-polarization relations. The cases of ront and rear reactant supply are treated. The treat-ment is extended to the case of a consecutive two-electron transfer reaction where the rate equation is rather complicated. Experimental results are pre-sented to test several aspects oi the model. The agreement between theory and experiment is generally good for moderate ohmic effects. Porous flow-through electrodes have several ad-vantages over porous diffusion electrodes mainly be-cause of the high mass transfer ates and high l imiting currents possible. It is, therefore, desirable to be abl