| 摘要 |
<p>The method consists of (a) mixing clay, such as kaolin or meta-kaolin, in finely-divided form, with excess aq. phosphoric acid at 100-150 deg. C until all the aluminium is dissolved, giving a soln. of Al(H2PO4)3 in phosphoric acid, with silica residues; (b) separating the siliceous solids to leave a transparent soln. of Al(H2PO4)3 in phosphoric acid; (c) adding sufficient alkaline sodium cpd to the clear soln. at 75-105 deg. C to form the cpd. of formula NaAl3H14(PO4)8.4H2O; and (d) recovering this crystalline cpd.</p> |
