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 [Bi۳+], [NaCl], temperature, and cathodic current density. In addition, cell voltage and current efficiency as two responses have been considered. An orthogonal array L۹, 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 [Bi۳+] (۷۵ g/L), [NaCl] (۲۵ g/L), temperature (۶۵°C) and current density (۱۰۰ A/m۲). 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.

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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 [Bi۳+] , [NaCl] , temperature , and cathodic current density. In addition , cell voltage and current efficiency as two responses have been considered. An orthogonal array L۹ , 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 [Bi۳+] (۷۵ g/L) , [NaCl] (۲۵ g/L) , temperature (۶۵°C) and current density (۱۰۰ A/m۲). 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