Investigation of the effects of polyelectrolyte coatings on colloid transport in porous media. Progress report, August 1, 1992--July 31, 1993

摘要

Goal is to study the repulsive interaction forces between humic- coated colloids and negatively charged porous media surfaces. Filtration experiments were carried out on hematite coated with humic acid or NOM, in porous media or packed bed (silica bed). Effects of Ca(sup 2+) are being studied. Results so far indicate that many humic coating properties (molecular size, acidity, polarity, surface conformation) have an important effect on colloid attachment rates but very little effect on colloid electrophoretic mobility; steric repulsive forces are proposed to account for these observations. Some humic coatings are more effective in enhancing colloid transport in quartz beds than in enhancing colloid stability. Other effects are discussed.