Dissolution regularities of smithsonite in methane sulfonic acid

摘要

Methane sulfonic acid (MSA) was proposed as a clean and efficient leaching agent to extract zinc from smithsonite. Experimental variables such as acid concentration, reaction temperature, particle size, and stirring speed were considered. Results indicated that zinc leaching fraction increased with increased MSA concentration, reaction temperature, stirring speed, and decreasing particle size. The dissolution kinetics of smithsonite in MSA solutions was investigated with respect to the corresponding experimental data and kinetics was analyzed using a new variant of the shrinking core model, in which both interfacial transfer and diffusion across the product layer affected the dissolution rate. The apparent activation energy of this process was determined to be 32.66 kJ/mol, and a semi-empirical rate equation was obtained to describe the process.