This Is AuburnElectronic Theses and Dissertations

Exploring actinide chemistry: uranyl detection and thorium catalysis




Tutson, Charmaine

Type of Degree

PhD Dissertation


Chemistry and Biochemistry


In a world where there is a strong need to improve our means of producing energy to sustain our ever expanding population with low green-house emissions, nuclear power offers sustainability and low greenhouse emissions, but needs appropriate measures to be taken to harness its power and minimalize its environmental impact. The presence of the common contaminant, uranyl, a dioxy cation of 6+ uranium with an overall 2+ charge, needs to be readily identified, thus, the ability to chelate very specifically these metal ions has applications in the nuclear energy production, remediation, and waste disposal fields. Along with this, the ability to extract uranyl from environmental media, aqueous and soil matrices, would aide in clean-up. The ease of preparing salen ligands and their ability to form stable metal complexes, coupled with the fluorescence of 2-quinoxalinol allows for the synthesis of a variety of salen 2-quinoxalinol ligands capable of serving as metal chelators for uranyl. The first portion of this work focused on developing solid phase extractors for uranyl by loading the salen 2-quinoxalinol ligands onto a solid substrate and exploring its ability to extract uranyl from aqueous samples. The second portion explored the ability of imidazole derived ligands, a common by-product produced during the synthesis of the salen 2-quinoxalinol derived ligands, to serve as chemosensors for uranyl. Expanding our fundamental knowledge of the 5-f elements is a growing area of research. Elucidating the chemical properties of these atoms allows for increased application in the nuclear field through helping the clean-up process by separating common lanthanides from present actinides, as well as in other areas of chemistry by finding ways to harness these properties in new and developing areas of research. Here, we explore the use of thorium nitrate as a simple actinide salt catalyst for the oxidative coupling of ortho-phenylenediamine to produce 2,3-diaminophenazine. The presence of the lone pairs on the amine groups of ortho-phenylinediamine and the pi-orbitals of the double bonds lead us explore other derivatives containing lone pairs or pi orbitals to determine if thorium nitrate was capable of coupling them.