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Title: The sorption behavior of Cs and Cd onto oxide and clay surfaces

The sorption behavior of Cs and Cd onto oxide and clay surfaces The sorption of Cs and Cd on model soil minerals was examined by complementary analytical and experimental procedures. X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance (NMR) spectroscopy were used to characterize the chemical and physical nature of Cs-reacted soil minerals. Cd and Cs adsorption isotherms for kaolinite were also measured at variable pH and temperature to establish likely reaction stoichiometries, while atomic force microscopy (AFM) was used to characterize the microtopography of the clay surface. XPS analyses of Cs-exchanged samples show that Cs is sorbed at mineral surfaces and at the interlayer site of smectite clays, although the spectral resolution of XPS analyses is insufficient to differentiate between basal, edge or interlayer sites. {sup 133}Cs MAS-NMR results also show that Cs is adsorbed primarily in an interlayer site of montmorillonite and on edge and basal sites for kaolinite. Cd adsorption isotherms on kaolinite were found to be additive using Al{sub 2}0{sub 3} + Si0{sub 2} Cd binding constants. AFM quantification of kaolinite crystallites suggest that edges comprise up to 50% of the BET surface area, and are consistent with NMR and surface charge results that Cs an Cd adsorption occur primarily at edge sites.
Authors: ; ; ; ; ;
Publication Date:
OSTI Identifier:37755
Report Number(s):SAND--95-0272C; CONF-950216--75
ON: DE95008531; TRN: 95:009606
DOE Contract Number:AC04-94AL85000
Resource Type:Conference
Data Type:
Resource Relation:Conference: Waste management `95, Tucson, AZ (United States), 26 Feb - 2 Mar 1995; Other Information: PBD: [1995]
Research Org:Sandia National Labs., Albuquerque, NM (United States)
Sponsoring Org:USDOE, Washington, DC (United States)
Country of Publication:United States
Language:English
Subject: 05 NUCLEAR FUELS; 54 ENVIRONMENTAL SCIENCES; CESIUM 133; RADIOACTIVE WASTE DISPOSAL; ADSORPTION; CADMIUM; CLAYS; OXIDES; LOW-LEVEL RADIOACTIVE WASTES; SOILS; KAOLINITE; CORUNDUM; MONTMORILLONITE; GIBBSITE