| 摘要 |
PURPOSE:To produce high-purity beta-MnO2 at a low cost, by adding nitric acid to Mn2O3 obtained by the thermal decomposition of electrolytic manganese dioxide or a chemically synthesized manganese dioxide, and repeating the thermal treatment of the mixture twice or more. CONSTITUTION:gamma-MnO2 such as the easily and economically available electrolytic manganese dioxide or chemically synthesized manganese dioxide is used as a starting raw material, and is preparatorily subjected to the thermal decomposition to release oxygen and obtain Mn2O3. The temperature of the thermal treatment is preferably about 500-800 deg.C. The obtained Mn2O3 is mixed with nitric acid, and subjected to the thermal treatment twice or more. The temperature of the thermal treatment is preferably about 170-500 deg.C, and the amount of the nitric acid is preferably about >=0.52g-equivalent. High purity beta-MnO2 having a particle diameter of about 1mum and free from the impurities such as Mn2O3 can be produced by the above process. |
