Flow-Through Porous-Electrode Model - Application to Metal-Ion Removal from Dilute Streams

Abstract

A one-dimensional model for flow-through porous electrodes operatingabove and below the limiting current of a metal deposition reaction has beendeveloped. The model assumes that there is one primary reactant species in anexcess of supporting electrolyte, and that a simultaneous side reaction mayoccur. The model predicts nonuniform reaction rates due to ohmic, mass-transfer,and heterogeneous kinetic limitations; the effects of axial diffusion anddispersion are included. Results are compared with the experimental data observedby various authors for the deposition of copper from sulfate solutionswith the simultaneous generation of dissolved hydrogen. Satisfactory agreementbetween model predictions and experimental data on over-all reactorperformance and deposit distributions has been accomplished. For an upstreamcounterelectrode, distributions of reaction rate (for both single andmultiple reactions), concentration, and potential describe the detailed systembehavior.