Na^+和K^+对过饱和铝酸盐溶液均相成核过程的影响  

The Influence of Na^+ and K^+ on the Homogeneous Nucleation of Al(OH)_3 Crystal from Supersaturated Caustic Aluminate Solution

作　　者：马春红[1] 刘常青[1] 尹周澜[1] 

机构地区：[1]中南大学化学化工学院,长沙410083

出　　处：《有色金属（冶炼部分）》2009年第6期24-27,共4页Nonferrous Metals（Extractive Metallurgy)

基　　金：国家自然科学重点基金资助项目(520476107)

摘　　要：采用原位电导跟踪仪分别检测了铝酸钠和铝酸钾溶液的均相成核诱导期,考察了Na+、K+对均相成核过程的影响。结果表明:60℃时,Na+、K+显著影响溶液的均相成核诱导期,相同过饱和度下的铝酸钠溶液成核速率快于铝酸钾溶液;成核反应级数均为4,临界固-液界面能为31.8 mJ/m2,与阳离子无关。这表明阳离子参与了溶液成核过程的铝酸根离子重构和基元生成,但不影响成核的控制步骤。The homogeneous nucleation induction period of AI（OH）3 crystal from supersaturated caustic aluminate solution was measured with in-situ conductivity meter respectively. Results show that the influence of Na^＋ , K^＋ on the induction period is apparent. The nucleation rate of sodium aluminate solution was faster than that of potassium aluminate solution. The nucleation kinetics of these two solutions showed a fourth-order dependence upon A1203 relative supersaturation, the critical interfacial energy is 31.8 mJ/m^2 and independent of alkali ion. It can he concluded that, Na^＋ , K^＋ take part in the reconstruction of alminate ions and the formation of growth units but has little effect on the controlling step.

关 键 词：铝酸盐溶液 NA^+ K^+ 均相成核 诱导期 

分 类 号：O643.12[理学—物理化学]