Production of ultra-pure manganese carbonate

• Grant number: 97/06574-4
• Support Opportunities: Research Grants - Innovative Research in Small Business - PIPE
• Start date: January 01, 1998
• End date: October 31, 2000
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Extractive Metallurgy
• Principal Investigator: Silvio Benedicto Alvarinho
• Grantee: Silvio Benedicto Alvarinho
• Company: Fermavi Eletroquímica Ltda (FERMAVI)

Abstract

The purpose of this research is to develop a production process for ultra-pure manganese carbonate for use in magnetic ceramics. Two courses of action will be assessed. The first is through leaching manganese monoxide with an ammonium carbonate solution. The manganese is mixed as an anion and made soluble, when the ammonium content is above a given level. Lowering the ammonia content, the manganese is precipitated as a very pure carbonate. The process developed by Dr. R. S. Dean of the U.S. Bureau of Mines, sought, in its original form, to take advantage of low-content, American manganese ore for use in steelmaking. Although very pure, the carbonate this process produces still does not attain the levels that are desirable for use in electronics. Preliminary studies have shown that the introduction of supplementary purification stages has a high probability of achieving a purer form of carbonate. The second course of action for the process aims to improve the classic method of producing manganese carbonate based on a reaction of manganese sulfate in solution with ammonium carbonate. Using this method, it is intended to purify the manganese sulfate solution through adsorption and crystallization. (AU)