Date of Award
Master of Science (MS)
Environmental Engineering and Science
Powell, Brian A.
Husson, Scott M.
DeVol, Timothy A.
Trace elemental and isotopic analysis of actinides via Thermal Ionization Mass Spectrometry (TIMS) is often difficult and time consuming due to intensive sample preparation. Polymer thin films show strong potential for rapid concentration of radionuclides from solution that may prove as suitable substrates for TIMS analyses. In this work, a polymer thin film (~180 nm) was coated onto a silicon substrate and utilized for rapid radioanalytical analysis. The polymer is composed of poly(vinyl benzyl chloride) functionalized with triethyl amine (TEA) to produce an anion-exchange site for concentrating anionic actinide complexes (i.e. PuCl62-, Pu(NO3)62-) from solution. In addition, selectively functionalizing â€œspotsâ€ with TEA creates hydrophilic regions and allows for concentration of an aqueous drop when surrounded by the hydrophobic polymeric backbone. Batch uptake studies were performed using inductively coupled plasma mass spectrometry, liquid scintillation counting and alpha spectrometry to determine uptake kinetics and anion-exchange capacities of the polymer thin film. Results indicated that along with a potential for utilization as a TIMS substrate, the polymer thin film yields high resolution alpha spectra, comparable to samples produced via electrodeposition. An apparent equilibrium constant (Kd) for the functionalized polymer was found to be approximately 9060 L/kg from 9M HCl. The anion exchange capacity of the film was determined using 36Cl uptake studies and found to be 1.25 x 10-1 Â± 1.07 Ã— 10-2 meq/gpolymer. Thus, the rapid uptake kinetics, good anion-exchange capacity, and high-resolution alpha spectra show good promise for the use of this thin film for rapid radioanalytical analyses.
Locklair, William, "Uptake of Plutonium on a Novel Thin Film for Use in Spectrometry" (2015). All Theses. 2272.