PRODUCTION OF MAGNESIUM HYDROXIDE

摘要

PURPOSE:To obtain Mg(OH)2 free from deposition of scale such as gypsum in the reaction with sulfuric acid, by adjusting the molar ratio of a silica component to Ca component containing natural magnesite to a level lower than a specific level, baking the mixture and subjecting the formed MgO to hydration reaction with warm water. CONSTITUTION:The molar ratio or SiO2 to the CaO component existing in the above magnesite is adjusted to <=2 in terms of Ca/Si. The control of the molar ratio is performed by the management of the grade of raw materials or by the addition of SiO2. The adjusted magnesite is baked between 850 deg.C and preferably 1200 deg.C to form an inert CaO-MgO-SiO2 mineral. The MgO formed by the baking process is subjected to hydration reaction with warm water. An Mg(OH)2 free from the deposition of scale such as gypsum and suitable for the neutralization of sulfuric acid or various desulfurization processes can be produced by this process.