DLVO theory and clay aggregate architectures formed with AlCl3

To understand the conditions in which clay aggregates with a different arch itecture can be formed, sedimentation experiments were undertaken of kaolin ite and montmorillonite suspensions mixed with Al electrolyte. The aggregat es' architecture was observed in a scanning electron microscope after super critical drying with liquid CO2 and relatively acceptable correlation with the value of the zeta potential of the clay particles was obtained. Hence, in a first approximation, it appeals that the texture of clay aggregate is driven by electrostatic interactions between particles, as expressed in the Derjaguin, Landau, Verwey and Overbeek (DLVO) theory. The main aggregate a rchitectures which were observed included sediments with a relatively unifo rm porosity formed by accumulation of particles under gravity, such as with out any Al electrolyte, and flocs with an architecture qualitatively consis tent with diffusion limited aggregates (DLA), when Al electrolyte were adde d to the suspension. (C) 1999 Published by Elsevier Science Limited. All ri ghts reserved.