ドロマイトを用いたアルミン酸ソーダ溶液の脱ケイ酸処理について
1968 年 84 巻 958 号 p. 123-128
詳細
1968 年 84 巻 958 号 p. 123-128
The removal of silica dissolved in sodium aluminate solution is one of the serious problems in production of highly purified alumina. The solution used here was prepared by leaching the laterite ore roasted with Na2CO3. Among various addition agents so far used for, removal of silica, it was found that the dolomite gave the best results and about 99% of silica was removed as a result of heat treatment of the solution in autoclave at 170°C, thus resulted in less than 0.03 as a value of SiO2×100/Al2O3 in the solution. The products formed by addition of dolomite powder contained calcium silicate hydrate, calcium aluminum hydroxide and basic aluminum silicate besides excess dolomite.
