Process for the extraction and elimination of deleterious material from natural manganese dioxide and concentrate of manganese dioxide obtained by said process

摘要

This invention relates to a new process for the extraction and elimination of deleterious material present in natural manganese dioxide (NMD), as well as in natural manganese dioxide obtained by such process. The process involves treating NMD with a HCl and water mixture in a reactor while stirring and heating the mixture. The heating temperature of the reactor is maintained in a predetermined range. The reactor is then fed with an amount of crushed NMD ore. A leaching reaction of said NMD ore with the HCl is produced by leaching for a period of time. Subsequently, the contents of the tank are filtered, washed and dried to recovery the concentrate of manganese dioxide substantially free of deleterious material.