Dissolution kinetics of cerussite in an alternative leaching reagent for lead

摘要

The dissolution kinetics of cerussite was investigated using methanesulphonic acid (MSA) as an alternative leaching reagent. The effects of particle size, stirring speed, acid concentration, and reaction temperature on the lead dissolution rate were determined. The dissolution process followed the kinetic law of the shrinking-core model, and a corresponding mixed control model was found suitable for representing the rate-controlling step. The mixed kinetic model comprised two stages: surface chemical reaction (283 K to 303 K) and diffusion through the product layer (303 K to 323 K). The activation energies of these sequential stages were 43.20 kJ mol(-1) and 17.20 kJ mol(-1), respectively. The corresponding dissolution kinetic equations are also presented to describe the dissolution reaction. The results indicated that methanesulphonic acid could be used as an effective leaching reagent for extracting lead from cerussite minerals. (C) 2014 Institute of Chemistry, Slovak Academy of Sciences