高苛性比铝酸钠溶液中硅、铝分离的研究

A STUDY ON SEPARATION OF SILICA AND ALUMINIUM IN HIGH CAUSTICITY RATIO ALUMINATE SOLUTION

通过热力学分析和实验，证明了在含硅高（ＳｉＯ２＞７０ｇ／Ｌ）、苛性分子比高（αｋ＞５０）的铝酸钠溶液中，控制一定的温度、溶液苛性分子比值和适量的石灰添加量，可以使溶液中的硅酸根离子［ＳｉＯ２（ＯＨ）２］２－以硅灰石的形式沉淀析出，而铝仍然保留在溶液中，不会造成铝的损失，顺利地实现溶液中硅铝的分离。

Based on the reference and thermodynamic analysis, the separation of silica and aluminium in high causticity ratio aluminate solution with a high SiO2 content is systematicalls studied. The results show that [SiO2(OH)2] can be precipitated as wollastonite and aluminium retained in the solution by oppropriate control of temperature, Ca/Si molar ratio and lime dosage, thus achieving a smooth separation of silica and aluminium.