Abstract

PARRA-MESA, C.M. et al. Process Optimization for Valuable Metal Recovery from Dental Amalgam Residues. Ing. invest. y tecnol. [online]. 2009, vol.10, n.3, pp. 217-226. ISSN 1405-7743.

In this paper, the methodology used for optimizing leaching in a semi pilot plant is presented. This leaching process was applied to recover value metals from dental amalgam residues. 2³ factorial design was used to characterize the process during the first stage and in the second one, a central compound rotational design was used for modeling copper percentage dissolved, a function of the nitric acid concentration, leaching time and temperature. This model explained the 81% of the response variability, which is considered satisfactory given the complexity of the process kinetics and, furthermore, it allowed the definition of the operation conditions for better copper recovery, which this was of 99.15%, at a temperature of 55°C, a concentration of 30% by weight and a time of 26 hours.

Keywords : Experimental design; factorial design; dental amalgam; leaching; optimization.