Recovery of Zinc and Manganese from Spent Alkaline Batteries via Hydrometallurgical Leaching Process

Abstract

The increasing disposal of spent alkaline batteries has generated significant environmental concerns due to the presence of hazardous metals and the loss of valuable recyclable resources. The present study investigates the recovery of zinc and manganese from spent alkaline batteries through a hydrometallurgical leaching process under controlled operational conditions. The research focuses on evaluating metal extraction efficiency, leaching kinetics, reagent consumption, and process optimization associated with sustainable battery recycling technologies. Experimental analysis was conducted to examine the influence of leaching agent concentration, temperature, solid-to-liquid ratio, reaction time, and agitation intensity on zinc and manganese dissolution behavior. Results demonstrate that hydrometallurgical leaching effectively dissolves zinc and manganese compounds from spent battery materials through acid-assisted metal extraction mechanisms, resulting in substantial metal recovery efficiencies. The study further reveals that optimized leaching conditions significantly improve extraction performance while minimizing secondary waste generation and chemical consumption. Increased reaction temperature and controlled acid concentration were found to accelerate dissolution kinetics and enhance metal recovery rates. Comparative assessment with conventional pyrometallurgical recycling methods confirms the advantages of hydrometallurgical processing, including lower energy requirements, improved metal selectivity, and reduced atmospheric emissions. In addition, the recovered zinc and manganese exhibit potential for reuse in battery manufacturing, metallurgical operations, and other industrial applications, supporting circular economy and resource conservation practices.