PILOT PLANT STUDIES FOR THE PRODUCTION OF ELECTROLYTIC MANGANESE DIOXIDE AND MANGANESE METAL

Abstract

India has vast deposits of low, medium and high grade manganese ores. Unfortunately, the minerals do not occur in the form in which they are primarily required to function as an effective depolarizer. Indian deposits mostly occur as pyrolusite, cryptomelane, psilomelane, manganite, etc. It became necessary to develop processes to utilize Indian manganese ores for production of electrolytic manganese dioxide (EMD), electrolytic manganese metal (EMM), activated manganese dioxide (AMD) and manganese sulphate monohydrate. The National Metallurgical Laboratory, Jamshedpur, India has established a 50kg/day electrolytic manganese dioxide and 50 kg/day electrolytic manganese metal pilot plant. Various manganese ores from different parts of India and abroad have been tested in the pilot plant, using various equipment and materials of construction. Relative effects of the different stages of the process, working conditions, quality of the product, etc., have been investigated and flowsheets have been made, including one for the simultaneous production of activated and electrolytic manganese dioxide. The products have been tested by various potential users. The technology has been transferred within India and abroad. Data on typical manganese ores tested in the pilot plant, analysis of the products, materials for anodes and cathodes, raw materials and utilities required per tonne of product and other information are presented.