微细粒高岭石在水介质中的聚团行为

通过采用沉降法以及颗粒表面动电位测试，考察了水介质中PH的变化以及阳离子表面活性剂对微细粒高岭石颗粒聚团行为的影响．结果表明：pH〈7时，水介质中高岭石颗粒表现为强烈的聚团行为；pH〉9时，主要以分散为主．阳离子型表面活性剂的加入使颗粒表面动电位增大，显著提高了高岭石的聚团效果．随表面活性剂浓度的增大，高岭石的聚团行为更加显著．pH=7时，烷基伯胺醋酸盐随着碳链的增长，对高岭石的聚团效果减弱；同一浓度下季胺盐的聚团效果优于烷基伯胺盐．

Aggregation Behavior of Ultrafine Kaolinite in Water

The change of pH and the effect of cationic surfactants on aggregation behavior of ultrafine kaolinite in the water were investigated by sedimentation tests and Zeta potential measurements. The experimental results show that kaolinite particles aggregate when the pH of system is less than 7 and disperse when the pH of system is more than 9. With the addition of cationic surfactants, the value of Zeta potential of kaolinite increase and the aggregation effect is improved. The higher the surfactant concentration is, the more obvious the aggregation effect is. While pH is 7, the sediment yield of kaolinite decreases with the increase of length of alkylamine acetate chains . At the same concentration, the quaternary ammonium compounds produce better aggregation effect than alkylamine acetate.