| 摘要 |
<p>A process for the production of a magnesium oxide, which comprises (A) reacting a water-soluble magnesium salt with not more than 0.95 equivalent weight, per equivalent weight of the water-soluble magnesium salt, of an alkaline substance at a temperature of not more than 40 DEG C, (B) heating the resultant reaction product and its reaction mother liquor at 50 to 120 DEG C to form a magnesium hydroxide, (C) forming the magnesium oxide into particles having an average secondary particle diameter of 5 to 500 mu m using a spray drier, (D) firing the particles at 1,100 to 1,600 DEG C, and (E) pulverizing the resultant fired particles under conditions which do not substantially destroy the average secondary particle diameter obtained in step (C). The magnesium oxide obtained as above has further improved hydrolysis resistance, since the surface of magnesium oxide crystals exposed on the surface of the fired and pulverized product obtained at the step (E) is coated with silica or a reaction product between silica and magnesium oxide.</p> |
