Abstract
To study the factors influencing the polarization characteristics of a flow-through electrode with electro-conductive particles, theoretical analyses have been made by the one-dimensional expression of a two-phase model with combinations of the general electro-chemical reaction rate and the fundamental equation of fluidization state. Potential, overpotential and effectiveness factor of the bed were studied for two systems, fast electrode reaction and slow electrode reaction. To indicate the performance of polarization characteristics of the particulate electrode, bed overpotential was introduced.
Experimentally, potential profiles and polarization curves were measured in the particulate electrode with graphite particles by using the reduction of ferricyanide in alkaline solution. The variation of polarization curves with changing bed expansion were well explained by the calculated results with an available fraction of surface area of electrode of f= 0.38.
