Structural and Electrosurface Properties of Iron-Containing Porous Glasses in NaCl Solutions. II. Surface Charge and Electrokinetic Potential of Porous Glasses

Resumo

Equilibrium electrosurface characteristics (surface charge and electrokinetic potential) have been determined for porous glasses with different compositions (magnetite-containing and magnetite-free glasses) in solutions of an indifferent electrolyte (NaCl). It has been revealed that the incorporation of iron oxide into the glass matrix increases the absolute value of the surface charge of the composite material relative to high-silica porous glass obtained from basic sodium borosilicate glass. The electrokinetic potentials determined from a set of experimental data on the streaming potential, electrophoretic mobility of porous glass particles, their specific electrical conductivity, and the structure of the pore space have been analyzed. It has been found that freshly prepared iron-containing glass samples and those exposed in electrolyte solutions for a long time have different electrokinetic characteristics.