Spectral induced polarization of Na-montmorillonite dispersions

Philippe Leroy (1) , Guillaume Mériguet (2) , S Huisman (3) , E Zimmermann (3) , M Weigand (4) , C Tournassat (1) , Mohamed Bizi (1) , A. Kemna (5)

1 BRGM - Bureau de Recherches Géologiques et Minières (BRGM)
2 PECSA - Physicochimie des Electrolytes, Colloïdes et Sciences Analytiques
3 Forschungszentrum Jülich GmbH | Centre de recherche de Juliers
4 University of Bonn
5 Department of Geophysics [Bonn]

Montmorillonite has remarkable adsorption properties because of its high specific surface area and surface charge density. Its surface charge distribution is also anisotropic. The basal faces have a negative and permanent surface charge due to isomorphic substitutions in the crystal and the edge faces have a pH-dependent surface charge due to amphoteric surface sites. We propose low-frequency complex impedance measurements of Na-Mt dispersions in the unexplored frequency range [Hz kHz] to get information on surface charge distribution, size and shape of Na-Mt dispersions at various particles concentrations (weight fractions 0.5 to 5%), salinities (from 10-4 to 10-2 M NaCl), and pH (5 to 10).

Domaines: Planète et Univers [physics]; Sciences de la Terre; Géochimie

Philippe Leroy, Guillaume Mériguet, S Huisman, E Zimmermann, M Weigand, et al.. Spectral induced polarization of Na-montmorillonite dispersions. Goldschmidt 2016, Jun 2016, Yokohama, Japan. ⟨hal-01280362⟩