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This article describes an experimental study about the spouted
bed electrodes which can be used for the electrolytic recovery
of metal from dilute aqueous solution. It is shown that spouted
bed may be used as three-dimensional electrode whose
hydrodynamic behavior provides all the good properties of
packed and fluidized bed electrodes and simultaneously
eliminates their disadvantages and restrictions. Two-type
current feeders(plain plate and bended plate) are designed to
operate the experiments about polarization curves. The limiting
current is observed from the polarization curve,then the mass
transfer coefficient can be calculated under the diffusion-
controlled condition. About current-potential curves in the
absence of particles in the electrode, we can obtain the values
of limiting current to calculate the mass transfer
coefficients. With glass beads in the electrode, it will
represent the similar results. For the experiment with active
conducting bed the problem of non-uniform potential
distribution and hence the loss of well-defined limit- ing
plateau on the i-E curves is encountered. Using the batch
circulation operation, provides another method to calculate the
mass transfer coefficients for active conducting particles in
the electrode. Furthermore,the measurement of potential drop is
also performed , and then it shows the two-dimensional
potential distribution. From the distribution, we find that the
main reaction zone is located at the spouted region.
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