Modeling of Cation Binding in Hydrated 2:1 Clay Minerals - Final Report

Technical Report · Thu Sep 14 04:00:00 EDT 2000

DOI:https://doi.org/10.2172/781155· OSTI ID:781155

Smith, David E ^[1]

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1. New Mexico State University

Hydrated 2:1 clay minerals are high surface area, layered silicates that play a unique role in determining the fate of radionuclides in the environment. This project consisted of developing and implementing computer simulation methods for molecular characterization of the swelling and ion exchange properties of Hydrated 2:1 clay minerals, and the subsequent analysis and theoretical modeling with a view toward improving contaminant transport modeling as well as soil remediation and radionuclide containment strategies. Project results included the (a) development of simulation methods to treat clays under environmentally relevant conditions of variable water vapor pressure; (b) calculation of clay swelling thermodynamics as a function of interlayer ion size and charge (calculated quantities include immersion energies, free energies, and entropies of swelling); and (c) calculation of ion exchange free energies, including contributions from changing interlayer water contents and layer spacing.

• Research Organization: New Mexico State Univ., Las Cruces, NM (US)
• Sponsoring Organization: USDOE Office of Environmental Management (EM) (US)
• DOE Contract Number: FG07-96ER14697
• OSTI ID: 781155
• Report Number(s): DOE/ER/14697; Project Number 54823; Project Number 54823
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
36 MATERIALS SCIENCE
54 ENVIRONMENTAL SCIENCES
CLAYS
COMPUTER SIMULATION METHODS
COMPUTERIZED SIMULATION
CONTAINMENT SYSTEMS
HYDRATED 2:1 CLAY MINERALS
HYDRATES
ION EXCHANGE
MOLECULAR CHARACTERIZATION
RADIONUCLIDE CONTAINMENT
RADIONUCLIDE MIGRATION
REMEDIAL ACTION
SILICATES
SOIL REMEDIATION
SOILS
SURFACE AREA
SWELLING
THEORETICAL MODELING
THERMODYNAMICS
WATER VAPOR