文档介绍：中国有色金属学报990237
中国有色金属学报
THE CHINESE JOURNAL OF NONFERROUS
METALS
1999年第9卷第2期 1999
高苛性比铝酸钠溶液中氧化铝的回收①
李小斌刘桂华彭志宏张传福何伯泉刘祥民
摘要对加入石灰后的高苛性比铝酸钠溶液中氧化铝的回收进行了研究。热力学
计算结果表明, 氧化钙较氢氧化钙更容易使铝酸钠溶液中的铝酸根离子转化为水合铝
酸钙, 使铝酸钠溶液的平衡苛性比能达到很高的值; 水合铝酸钙随着温度的升高, 稳
定性降低, 因而能在拜尔法高温溶出过程中分解以代替石灰, 并回收其中的氧化铝。
实验结果表明, 影响水合铝酸钙形成因素的大小顺序为: 温度≈碱浓度>CaO/Al 2O3
>时间。
关键词铝酸钠溶液氧化钙水合铝酸钙
中图法分类号 TF821
RECOVERY OF ALUMINA IN HIGH MOLE RATIO
ALUMINATE SOLUTION
Li Xiaobin, Liu Guihua, Zhang Chuanfu, Peng Zhihong, He Boquan and Liu Xiangmin‧
Department of Nonferrous Metallurgy, Central South University of Technology,
Changsha 410083, P. R. China
‧ Zhongzhou Alumina Factory, Jiaozuo 454174, P. R. China
ABSTRACT The recovery of alumina in the high mole ratio (αk) aluminate solution was
studied. The thermodynamic calculation results indicated that the formation of calcium
aluminate hydrate from aluminate solution with CaO is easier than that with Ca(OH)2, and the
value of αk is great at low temperature; the temperature rise leads to the reduction of stability of
calcium aluminate hydrate in the aluminate solution, and it can be posed at high
temperature, which can both substitute for Ca(OH)2 and recover alumina in the process of
Bayer. The order of affecting the formation of calcium aluminate hydrate is as follows:
temperature≈concentration of caustic soda>CaO/Al 2O3 (mole