Determining the Extraction Efficiency for Removing Tritiated Water from Silica Gel Using a Solvent Dilution Technique
M. Ruggieri, M. A. Davi, H. H. Tran
Silica gel is used as a desiccant to collect water vapor to measure air concentrations of tritiated water. A simple economic technique using solvent dilution has been employed at Lawrence Berkeley National Laboratory to quantify the amount of tritiated water contained on silica gel. Silica gel samples are equilibrated with a measured volume of de-ionized water, and an aliquot of the equilibrated water is removed and analyzed for tritium using a liquid scintillation counter. A study was conducted to evaluate this application of the solvent dilution technique. The results of this study indicate that the analysis of silica gel for tritiated water using a solvent dilution technique can produce tritium extraction recoveries above 95%. Varying silica gel amounts, types, and initial silica gel water contents did not significantly affect recovery yields. These results verify that a solvent dilution method can be used effectively for quantifying tritiated water on silica gel when the initial water content of the silica gel is known (or can be estimated), and the diluted tritiated water concentration can be measured with liquid scintillation counting.
This abstract was presented at the 32nd Annual Midyear Meeting, "Creation and Future Legacy of Stockpile Stewardship Isotope Production, Applications, and Consumption", Analytical Techniques Session, 1/24/1999 - 1/27/1999, held in Albuquerque, NM.