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Characterization and thermogravimetric analysis of lanthanide hexafluoroacetylacetone chelates.

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.

SUBMITTER: Shahbazi S

PROVIDER: S-EPMC5219043 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

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Characterization and thermogravimetric analysis of lanthanide hexafluoroacetylacetone chelates.

Shahbazi Shayan S Stratz S Adam SA Auxier John D JD Hanson Daniel E DE Marsh Matthew L ML Hall Howard L HL

Journal of radioanalytical and nuclear chemistry 20160830 1

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-h ...[more]

PMID: 28111487

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