Characterization and thermogravimetric analysis of lanthanide hexafluoroacetylacetone chelates

Shayan Shahbazi; S Adam Stratz; John D Auxier 2nd; Daniel E Hanson; Matthew L Marsh; Howard L Hall

doi:10.1007/s10967-016-5005-0

Characterization and thermogravimetric analysis of lanthanide hexafluoroacetylacetone chelates

J Radioanal Nucl Chem. 2017;311(1):617-626. doi: 10.1007/s10967-016-5005-0. Epub 2016 Aug 30.

Authors

Shayan Shahbazi¹, S Adam Stratz¹, John D Auxier 2nd², Daniel E Hanson¹, Matthew L Marsh³, Howard L Hall²

Affiliations

¹ Department of Nuclear Engineering, University of Tennessee, 301 Middle Dr., Pasqua Nuclear Engineering Building, Knoxville, TN 37996 USA.
² Department of Nuclear Engineering, University of Tennessee, 301 Middle Dr., Pasqua Nuclear Engineering Building, Knoxville, TN 37996 USA ; Radiochemistry Center of Excellence, University of Tennessee, 1508 Middle Dr., Ferris Hall, Knoxville, TN 37996 USA ; Institute for Nuclear Security, University of Tennessee, 1640 Cumberland Ave. Howard Baker Jr. Center for Public Policy, Knoxville, TN 37996 USA.
³ Department of Chemistry, University of Tennessee, 1420 Circle Dr., Buehler Hall, Knoxville, TN 37996 USA.

Abstract

This work reports the thermodynamic characterizations of organometallic species as a vehicle for the rapid separation of volatile nuclear fission products via gas chromatography due to differences in adsorption enthalpy. Because adsorption and sublimation thermodynamics are linearly correlated, there is considerable motivation to determine sublimation enthalpies. A method of isothermal thermogravimetric analysis, TGA-MS and melting point analysis are employed on thirteen lanthanide 1,1,1,5,5,5-hexafluoroacetylacetone complexes to determine sublimation enthalpies. An empirical correlation is used to estimate adsorption enthalpies of lanthanide complexes on a quartz column from the sublimation data. Additionally, four chelates are characterized by SC-XRD, elemental analysis, FTIR and NMR.

Keywords: Hexafluoroacetylacetone; Lanthanides; Nuclear forensics; Rapid separations; Thermochromatography; Thermogravimetric analysis.