Results are reported of an experimental investigation of the effects of aqueous zinc(II) and sulfuric acid concentrations on current efficiencies and deposit morphologies of metallic zinc, aimed at designing a process for zinc recovery from solid industrial wastes by leaching and electrodeposition. Voltammetry and chronopotentiometry of additive-free solutions of zinc(II) sulfate and sulfuric acid were used to determine the zinc(II) reduction kinetics, prior to investigating the deposition in a Hull cell to observe the effects of the current density and the bath composition on current efficiencies and deposit morphologies. For a current density of 45 mA cm À2 , best performance was obtained with zinc(II) concentrations of the same order of magnitude as the H + concentration; too acidic solutions resulted in lower current yields and pronounced 3-D growth of the deposit.

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