Pillared montmorillonites: Cesium-selective ion-exchange materials

Journal Article · Wed Sep 01 04:00:00 EDT 1999 · Separation Science and Technology

DOI:https://doi.org/10.1081/SS-100100773· OSTI ID:691481

Sylvester, P; Clearfield, A; Diaz, R J ^[1]

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1. Texas A and M Univ., College Station, TX (United States). Dept. of Chemistry

A zirconia-pillared and an alumina-pillared montmorillonite clay were found to exhibit high K{sub d}S for trace levels of cesium (2.5 ppb) in the presence of high concentrations of Ca{sup 2+}, Mg{sup 2+}, and Na{sup +} ions with distribution coefficients (K{sub d}S) for {sup 137}Cs exceeding 1 {times} 10{sup 5} mL/g over a wide range of competing ion concentrations. An excess of K{sup +} ions, however, caused a dramatic reduction in the Cs K{sub d}S for both of the materials. These results were in contrast to the parent montmorillonite which exhibited far lower K{sub d}S for {sup 137}Cs, particularly in the presence of high concentrations of Mg{sup 2+} and Ca{sup 2+}. Batch tests in simulated groundwaters showed that both pillared clays efficiently removed {sup 137}Cs from solution, with the best K{sub d}S being approximately 8.5 {times} 10{sup 5} mL/g in a potassium-free groundwater. The materials performed less well in a groundwater with a high potassium concentration, but still gave K{sub d}S similar to commercially available zeolites. The rate of {sup 137}Cs uptake was found to be rapid with both the alumina- and zirconia-pillared clays extracting >90% of the {sup 137}Cs from a 0.1 M NaNO{sub 3} solution within 5 minutes.

• Sponsoring Organization: Oak Ridge National Lab., TN (United States)
• OSTI ID: 691481
• Journal Information: Separation Science and Technology, Journal Name: Separation Science and Technology Journal Issue: 12 Vol. 34; ISSN 0149-6395; ISSN SSTEDS
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
54 ENVIRONMENTAL SCIENCES
ALUMINIUM OXIDES
CESIUM
GROUND WATER
ION EXCHANGE
MONTMORILLONITE
RADIOACTIVE WASTE PROCESSING
REMEDIAL ACTION
SORPTIVE PROPERTIES
ZIRCONIUM OXIDES