Using Taguchi Method to Optimize Recovery of Bismuth by Electrolysis

This paper presents a methodology, based on the taguchi parameter design approach, for the optimization of process parameters for bismuth recovery from aqueous solutions. The process parameters considered are [Bi3+], [NaCl], temperature, and cathodic current density. In addition, cell voltage and current efficiency as two responses have been considered. An orthogonal array L9, the signal-to-noise (S/N) ratio, and the analysis of variance were used to analyze the effect of selected process parameters and their levels. From a metallurgical point of view, the separation and recovery of bismuth from a bismuth glance concentrate through leaching, purification and electrowining of chloride solutions were carried out. The optimum conditions for the selected parameter values were found as [Bi3+] (75 g/L), [NaCl] (25 g/L), temperature (65°C) and current density (100 A/m2). Finally, a mathematical model has been proposed and the results of a confirmatory run are reported to verify the results, which indicate that this methodology is more efficient in optimizing the process parameters.