Dissolution of zinc and manganese from spent zinc-carbon battery powder in acidic media

In this thesis, dissolution conditions and kinetics of zinc (Zn) and manganese (Mn) from waste zinc-carbon battery powder in sulphuric acid (H2SO4) medium were investigated. The experiments were carried out by agitation leaching. The effects of the stirring speed (0-600 rpm), H2SO4 concentration (0.1-0.5 M), temperature (30-70°C) and Fe+2 ion concentration (0.9*10-2 – 3.6*10-2 M) on Zn and Mn dissolution were investigated. According to the results obtained from experimental studies, it was determined that, the dissolution of Zn and Mn was directly proportional with stirring speed, H2SO4 concentration, temperature and Fe+ 2 ion concentration. As a result of the kinetic evaluations, the dissolution of Zn and Mn in H2SO4 medium from waste zinc-carbon battery powder was expressed by interface transfer and diffusion across the product layer. The activation energy for the dissolution of Zn and Mn was calculated as 28.63 kj/mol and 71.82 kj/mol, respectively. Zn dissolution was expressed with (stirring speed)1.27 and [H2SO4]0.80, Mn dissolution was expressed with (stirring speed)1.85and [H2SO4]0.65.