Award Date

May 2018

Degree Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry and Biochemistry

First Committee Member

Ralf Sudowe

Second Committee Member

Ken Czerwinski

Third Committee Member

Roger Henderson

Number of Pages

116

Abstract

Studies of the chemical properties of the heaviest elements have always been difficult due to the short half-lives and low cross sections involved. To solve this problem, atom-at-a-time methods are necessary to determine the properties of these short-lived isotopes. Extremely fast kinetics for the chemical reactions studied (on the same order as the nuclide’s half-life) are required, and the system should have the potential for automation. Solvent extraction, with its selectivity and quick kinetics, has historically been used for these investigations into characteristics of super heavy elements. Another technique, extraction chromatography, offers potentially a way of investigating rutherfordium’s properties, without the solvent waste generated in liquid-liquid extractions. A rapid method involving the use of a ligand with high intragroup selectivity is necessary to discover more about rutherfordium. Studies with the homologs of rutherfordium, zirconium and hafnium, can be performed using liquid-liquid extractions as well as extraction chromatography. These investigations can then be used as a basis for comparison with future studies involving the transactinide element. Based on literature reviews, tertiary amines and phosphates show promise in extracting group 4 elements. In particular, tris(2-ethylhexyl)amine (TEHA) and tris(2-ethylhexyl)phosphate (TEHP) can be used to selectively extract zirconium, hafnium, neptunium, and plutonium from a chloride matrix. The results of a detailed study investigating the solvent extraction of Zr, Hf, and Pu from various mineral acids by these two ligands will be presented together with the use of extraction chromatography to separate these elements. The development of a suitable system for rutherfordium based on these extractants can help to further elucidate its properties.

Keywords

Hafnium; Plutonium; Separations; Zirconium

Disciplines

Chemistry

Language

English


Included in

Chemistry Commons

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