| 摘要 |
PURPOSE:To manufacture powder as a starting material for finely powdered spinel with low crystallinity by adjusting the pH of an aqueous soln. contg. Mg and Al compounds to form a precipitate in the presence of an alcohol and by calcining the precipitate. CONSTITUTION:A water soluble magnesium compound such as MgCl2.6H2O and a water soluble aluminum compound such as AlCl3.6H2O are dissolved in pure water. The resulting aqueous soln. is mixed with an alcohol such as methanol, ethanol or buranol, and the pH of the soln. is adjusted to about 10-11 by adding an alkali such as an aqueous ammonia soln. to precipitate Mg(OH)2, Al(OH)3 and the composite hydroxide of Mg and Al. This precipitate is calcined at about 400-900 deg.C to obtain the titled powder of MgAl2O4 (and Al2O3). |
