Patent ID: 6171562
Filing Date: 2001-01-09
Classification: C22B

Abstract:
A process for extracting and eliminating deleterious material from natural manganese dioxide (NMD) comprising:feeding a reactor with a solution consisting of HCl and water, heating said solution with stirring to a reaction temperature ranging from about 80.degree. C. to 95.degree. C. and maintaining the HCl concentration in said solution within a range of about 9% to 25% w/w;maintaining the temperature of said HCl solution in said reactor at a temperature of from about 80.degree. C. to 95.degree. C.;feeding said reactor containing said HCl solution with crushed NMD ore to provide a reaction pulp concentration of from about 10% to 40%;leaching said reaction pulp with said HCl solution for a period of about 10 to 60 minutes;filtering the contents of said reactor to recover the concentrate of manganese dioxide (MnO.sub.2); andwashing and drying the recovered concentrate of MnO.sub.2.