مرکز منطقه ای اطلاع رساني علوم و فناوري - Investigation of Dissolution of Zinc Powder Obtained Waste Alkaline Battery in Sodium Hydroxide Solutions

Abstract :

Metal contents of waste batteries can be recovered by metallurgical methods. One of these methods is hydrometallurgical route, and it involves the production of metal, metal salts and compounds by means of chemical reactions in aqueous solutions. First step of hydrometallurgy is leaching process containing a solid to liquid mass transfer. In the leaching process, solid material is dissolved by a solvent, and metal values are transferred into solution medium. In this study, it was investigated dissolution of zinc powder in waste alkaline batteries in sodium hydroxide solutions. In the experiments, the effects of solution concentration, reaction temperature, particle size of solid, solid to liquid ratio, and stirring speed on dissolution of battery powder were studied. It was found that the dissolution increased with an increase in concentration, reaction temperature and stirring speed, and with a decrease solid‐to‐liquid ratio and in particle size. According to the experimental results obtained, it can be said that the reaction rate and solution concentration compared to other parameters have an important effect on dissolution of zinc powder. At a solution concentration of 0,5 mol/L, it was determined that 19% of zinc in battery powder dissolved after 120 min of leaching time, while at a concentration of 2,5 mol/L, 99% of zinc dissolved only after 20 min of leaching time. It was found that the extent of leaching of zinc in battery powder was 96,7% to 98,3% when the temperature rose from 20 °C to 60 °C after 120 min and 30 min of leaching time, respectively.