Ionic diffusion in single crystals of vermiculite

Miscellaneous · Fri Jan 01 00:00:00 EST 1993

OSTI ID:6976191

Maraqah, H R

Novel guest-host compounds, based on single crystal vermiculite, were synthesized by diffusive techniques through a new hydrogen vermiculite. Single crystals were chosen because of the ease of characterization. An investigation of the ion transport properties of these single crystals was done to determine the mechanism of conductivity including the predominant charge carrier. Measurements of the ionic conductivity using impedance spectroscopy and X-ray lattice parameters of the ion-exchanged samples strongly suggest that the native cations and not protons are the major current carriers. Single crystals of hydrogen vermiculite were synthesized at room temperature by ion exchange from sodium-vermiculite using 1 molar acetic acid for a one week. Subsequent ion exchange with other cations was found to be much enhanced. Thus transition metals were exchanged in about a week in contrast to the need of several months using previous methods. The ionic conductivity of hydrogen vermiculite was measured and shown to be much lower than that of many other monovalent cations in the same host lattice. Its enthalpy of motion is also much lower. These marked differences suggest that protonic species do not play a significant role in charge transport in these layered materials. These materials were characterized by x-ray powder diffraction, thermogravimetric analysis and acid-base titration. Hydrogen-vermiculite was found to react with organic bases, like methylamine, ethylamine, n-butylamine, n-hexylamine, n-octylamine, n-decylamine, aniline, acrylamide, methacrylaminde, urea, 1,10phenanthroline, and 1,1phenanthroline ferrous sulfate complex, to undergo ion exchange with metal cations like sodium, zinc, copper(II) ions and polymerization reactions could be performed in the galleries of the structure like pyrrole and aniline. Its behavior was compared with that of powdered montmorillonite.

• Research Organization: State Univ. of New York, Binghamton, NY (United States)
• OSTI ID: 6976191
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
CATIONS
DIFFUSION
ORGANIC COMPOUNDS
POLYMERIZATION
TRANSITION ELEMENTS
ION EXCHANGE
VERMICULITE
PERMEABILITY
ELECTRICAL PROPERTIES
PHENANTHROLINES
THERMODYNAMIC PROPERTIES
AROMATICS
AZAARENES
CHARGED PARTICLES
CHEMICAL REACTIONS
ELEMENTS
HETEROCYCLIC COMPOUNDS
INORGANIC ION EXCHANGERS
ION EXCHANGE MATERIALS
IONS
MATERIALS
METALS
MICA
MINERALS
ORGANIC NITROGEN COMPOUNDS
PHYSICAL PROPERTIES
SILICATE MINERALS
360602* - Other Materials- Structure & Phase Studies
400201 - Chemical & Physicochemical Properties