The Diffusion of Interlamellar Water in the 23.3 Å Na-Montmorillonite:Pyridine/H2O Intercalate by Quasielastic Neutron Scattering

J. M. Adams, C. Breen and C. Riekel
Edward Davies Chemical Laboratories, University College of Wales, Aberystwyth, SY23 1NE, U.K.
Institut Laue-Langevin, 156X, Grenoble, Cedex, France

Abstract: The diffusion of water in the title intercalate has been measured by quasielastic neutron scattering. The diffusion coefficient (6.1 × 10−7 cm2 s−1 at 23.5°C) is one order less than that found previously for a sodium-exchanged montmorillonite which, however, contained 4 times as much water in the interlamellar space. The activation energy for the motion has been deduced to be 18 kJ mol−1. Also it has been demonstrated that upon the time scale of the neutron scattering events (faster than 10−9 s) the hydroxyl groups of the clay lattice are not in motion.

Key Words: Diffusion • Intercalate • Montmorillonite • Neutron • Pyridine • Quasielastic

Clays and Clay Minerals; April 1979 v. 27; no. 2; p. 140-144; DOI: 10.1346/CCMN.1979.0270211
© 1979, The Clay Minerals Society
Clay Minerals Society (www.clays.org)