(1. 中南大学 冶金科学与工程学院， 长沙 410083；
2. 中国铝业股份有限公司 山西分公司， 河津 043300)
摘 要: 为对高浓度铝酸钠溶液碳酸化分解过程中产品杂质含量的控制提供理论依据， 分析了铝酸钠溶液碳酸化分解过程的热力学， 认为该过程中Al(OH)3析出的真正机理是过饱和铝酸钠溶液的自发结晶； 而基于分解过程中平衡浓度的热力学计算表明， 在碳酸化分解过程中SiO2的变化规律与公认的三段变化规律一致， 说明该过程产品中SiO2的含量取决于它在溶液中的平衡浓度， 而非吸附所致； 同时还分析了丝钠铝石的形成热力学。
关键字: 铝酸钠溶液; 碳酸化分解; 热力学; 机理
aluminate solution
（1. College of Metallurgical Science and Engineering,
Central South University, Changsha 410083, China;
2. Shanxi Company, China Aluminium Corporation Ltd, Hejin 043300, China）
Abstract:The mechanism of carbonization process of aluminate solution was analyzed thermodynamically. The results show that the internal reason of precipitation of Al(OH)3 in the process is its spontaneous nucleation caused by supersaturation of aluminate solution. The behaviors of SiO2 in the process are in accordance with that from published experiment, which implies that the content of product SiO2 from carbonization depends on its solubility but is not the result of absorption. The thermodynamic calculation for forming Na2O·Al2O3·2CO2· nH2O was achieved.
Key words: aluminate solution; carbonization; thermodynamics; mechanism
