Positive electrokinetic charge of silica in the presence of chlorides

被引：83

作者：

Kosmulski, M

机构：

[1] Tech Univ Lublin, Dept Electrochem, PL-20618 Lublin, Poland

[2] Abo Akad Univ, Dept Chem Phys, FIN-20500 Turku, Finland

来源：

JOURNAL OF COLLOID AND INTERFACE SCIENCE | 1998年 / 208卷 / 02期

关键词：

silica; zeta potential; concentrated dispersion; specific adsorption; pristine point of zero charge; isoelectric point;

D O I：

10.1006/jcis.1998.5859

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The presence of chlorides promotes a positive electrokinetic charge of silica. Silica shows an isoelectric point (iep) at pH 2 in the presence of HCl but at pH < 1.5, if any, in the presence of HClO4 and HNO3. The iep of silica in the presence of different 1:1 salts depends on the nature and concentration of the salt. The highest value of pH, 5.5, was observed for 0.1 mol dm(-3) cesium chloride and nitrate. A larger increase in cesium salt concentration shifts the iep back to low pH values and at >0.5 mol dm(-3) there is no iep (only negative zeta potentials). (C) 1998 Academic Press.

引用

页码：543 / 545

页数：3

共 5 条

[1] Electrokinetic and direct force measurements between silica and mica surfaces in dilute electrolyte, solutions [J].