| 摘要 |
PURPOSE:To prepare a high-quality manganese dioxide for cell, having low beta- content, by oxidizing heavy manganese carbonate at specific temperature and pressure with an oxidizing gas comprising a steam-containing oxygen gas or dried oxygen gas. CONSTITUTION:Heavy manganese carbonate is prepared e.g. by the precipitation reaction of a soluble manganese salt with a soluble carbonate. The produced heavy manganese carbonate is oxidized under a reaction pressure of 4- 20 atm at 275-350 deg.C using steam-containing oxygen gas or dried oxygen gas as the oxidizing gas. The objective chemically synthesized manganese dioxide for cell, having an MnO2-content of >=88% and beta-content in the produced MnO2 of <=20% can be produced by this process. The dry cell manufactured by using the chemically synthesized manganese dioxide as a raw material is superior to those manufactured from electrolytic manganese dioxide in the continuous discharge characteristics, intermittent discharge characteristics, etc. |
