Al－Mg　MMH溶胶和钠土悬浮体的相互作用机理  

The Interaction Mechanism of Al-Mg MMH Sols with Na-montmorillonite Suspensions

作　　者：孙德军[1] 侯万国[1] 张春光[1] 韩书华[1] 王果庭[1] 

机构地区：[1]山东大学胶体与界面化学研究所

出　　处：《高等学校化学学报》1996年第9期1428-1432,共5页Chemical Journal of Chinese Universities

摘　　要：通过流变参数、电泳淌度和ｐＨ值的测定，研究了无机盐（ＣａＣｌ_２、ＫＣｌ、ＮａＣｌ）和ｐＨ值对铝镁混合金属氢氧化物与钠土悬浮体间相互作用的影响．发现随着混合金属氢氧化物含量的增加，钠土体系的ｐＨ值逐渐降低，而动切力（ＹＰ）先上升，经最大值后逐渐下降；当钠土体系为ＮａＣｌ所饱和时，相同混合金属氢氧化物加量下ＹＰ的上升幅度明显减小，在实验混合金属氢氧化物浓度范围内，ＹＰ未出现峰值。混合金属氢氧化物／钠土体系的ＹＰ随ｐＨ值的变化曲线呈抛物线形，加入相同浓度的无机盐，△ＹＰ、△ｐＨ（绝对值）按ＣａＣｌ_２＞ＫＣｌ～ＮａＣｌ次序递减。The effects of inorganic salts(NaCl,KCl and CaCl2)and pH values on the interaction between Al-Mg MMH sol(aluminum magnesium mixed metal hydroxides)and Na-montmorillonite(Na-Mt)suspensions have been studied by the measurments of rheology,electrophoretic mobility and pH. The results show that the increase of MMH in Na-Mt suspensions produced an increase in YP(yield point)at first and then a decrease after a maximum but a gradual decrease in pH.The results are interpreted as meaning that the MMH sols can interact with Na-Mt suspensions through an ion exchange mechanism. In the presence of saturated NaCl,a much less change of YP and no YP maximum under the experimental concentrations of MMH can be explained by DLVO theory. Due to the effects of pH on ion exchange reaction the change of YP with pH of MMH/Na-Mt systems is in terms of parabolic curve.Inorganic salts lower YP and pH in the order of CaCl2>KCl～NaCl,and the order is found to be consistent with that for experimental estimates of the number of unit layers in face-to-face association. This would imply that the metallic ions must function as the exchangeable cations.

关 键 词：铝 镁 金属氢氧化物 钠土悬浮体 流变学 

分 类 号：O648.22[理学—物理化学]