초록 ▼

Battery-grade MnO2 is produced by (a) treating a MnCl2 solution with Cl2 and Mg(OH)2 whereby obtaining a MgCl2 solution that contains a MnO2 precipitate; and said MgCl2 solution contains at least 85 g/l of magnesium (b) allowing to digest the precipitate in the MgCl2 solution in presence of Cl2 unde

Battery-grade MnO2 is produced by (a) treating a MnCl2 solution with Cl2 and Mg(OH)2 whereby obtaining a MgCl2 solution that contains a MnO2 precipitate; and said MgCl2 solution contains at least 85 g/l of magnesium (b) allowing to digest the precipitate in the MgCl2 solution in presence of Cl2 under pressure; (c) separating the digested precipitate from the solution; and (d) washing and drying the precipitate. Owing to step (b), operating conditions in step (a) may be such that a concentrated MgCl2 solution is obtained, which is important for the further processing of that solution by pyrohydrolysis.

대표청구항 ▼

A process for the production of battery-grade manganese dioxide which comprises: (a) contacting a manganese chloride solution with chlorine, while maintaining the pH of the solution between 0.5 and 3 by adding MgO and/or Mg(OH)2 so as to thereby produce a MgCl2 solution poor in manganese and which c

A process for the production of battery-grade manganese dioxide which comprises: (a) contacting a manganese chloride solution with chlorine, while maintaining the pH of the solution between 0.5 and 3 by adding MgO and/or Mg(OH)2 so as to thereby produce a MgCl2 solution poor in manganese and which contains a MnO2 precipitate that is contaminated by magnesium, the operating conditions being such that the produced MgCl2 solution contains at least 85 g./l. of magnesium, (b) allowing the MnO2 precipitate to digest in said MgCl2 solution in the presence of chlorine under pressure in an autoclave so as to reduce substantially the magnesium content of said MnO2 precipitate, (c) separating the digested MnO2 precipitate from the MgCl2 solution, (d) washing and drying the MnO2 precipitate.