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dc.contributor.advisorBurgess, Ianen_US
dc.creatorSigrist, Jessicaen_US
dc.date.accessioned2015-10-21T12:00:34Z
dc.date.available2015-10-21T12:00:34Z
dc.date.created2013-09en_US
dc.date.issued2015-10-20en_US
dc.date.submittedSeptember 2013en_US
dc.identifier.urihttp://hdl.handle.net/10388/ETD-2013-09-1219en_US
dc.description.abstractAt Cameco mine sites in northern Saskatchewan, naturally occurring elements of concern (EOC) such as As, Ni, Mo, and Se are present in uranium ore bodies. Ferrihydrite (Fh) is found in tailings management facilities (TMF) and is known to sequester arsenates and arsenites. Fh is known to be metastable and undergo phase transformations to goethite (α-FeOOH) and hematite (α-Fe2O3). Reductive conditions are known to be a driving force in Fh transformation and the release of adsorbed As species from the surface. This study uses electrochemistry to control reductive potentials applied to Fh adsorbed As species. Electrochemistry was coupled with attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy to determine the behaviour of adsorbed arsenate and arsenite on the Fh surface. The potentials required to desorb As(III) and As(V) from the Fh surface were negative enough to cause the reduction of water, thus increasing the pH of the solution through the generation of OH-. In order to measure the extent of the pH change a miniature palladium/palladium oxide pH sensor was fabricated in order to make in-situ pH measurements during spectroelectrochemical studies. Additionally, in-situ solution potential (Eh) measurements were made during potential control. It was found that potential induced pH and Eh changes were significant enough to release arsenite from the Fh surface. Arsenate was also found to desorb from Fh during the application of reductive potentials though successive deprotonation leading to a totally deprotonated As(V) species.en_US
dc.language.isoengen_US
dc.subjectATR-FTIR, Spectroelectrochemistry, Arsenic, Ferrihydriteen_US
dc.titleSpectroelectrochemical Studies of Adsorbed As(III) and As(V) on Ferrihydriteen_US
thesis.degree.departmentChemistryen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.grantorUniversity of Saskatchewanen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMaster of Science (M.Sc.)en_US
dc.type.materialtexten_US
dc.type.genreThesisen_US


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