| 摘要 |
PURPOSE:To produce beta-MnO2 having extremely high purity, by adding nitric acid to the product obtained by the thermal decomposition of manganese nitrate, and again carrying out the thermal decomposition if necessary twice or more. CONSTITUTION:Easily available manganese nitrate hexahydrate is subjected to the thermal decomposition at about 170-500 deg.C. If the thermal decomposition temperature is lower than about 170 deg.C, the degree of decomposition is insufficient, and when it is about >=500 deg.C, Mn2O3 may be produced as an impurity. The product obtained by the above thermal decomposition is added with preferably about >=0.52g-equivalent of nitric acid, and again subjected to the thermal decomposition by heating preferably at about 170-500 deg.C. High purity beta- MnO2 free from the impurities such as Mn2O3 can be produced by this process. The purity of the obtained beta-MnO2 can be further improved by repeating the second thermal decomposition two or more times. |
