Mass transfer rates between particles and electrolyte have been determined by means of the fixed or moving electrodes in the beds of conducting copper particles and of nonconducting glass beads which were fluidized by acidified copper solution. The experiment have been carried out with the variation of bed expansion, particle size, and bed height.
1） Mass transfer data with the active fluidized bed of conducting copper particles in the range 38<R_e,_p/1-ε<380 were correlated by the equation
j _Mε = 0.78（R_e,_p/1-ε）^-0.50(d_p/d_H)^-0.50
the Reynolds number（R_e,_p） is based on the particle diameter.
2） Mass transfer data within the fluidized bed of inert glass particles in the range 17<R_e,_p/1-ε<210 were correlated by the equation
j _Mε = 0.71（R_e,_p/1-ε）^-0.41(d_p/d_H)^-0.41
the d_H is the mean hydraulic diameter.