Presentation Type

Poster

Abstract

In today's world the need for a constant, easily obtainable power supply is an everyday challenge. One underutilized resource that the world has is nuclear power, namely nuclear fission. Currently there is an estimated 4.5 billion metric tons of naturally solubilized, fissile uranium in seawater, reaching concentration levels close to 3.3 ppb; approximately 1000 times the current estimated amount available for terrestrial mining. This opportunity to move away from terrestrial mining presents both economic and environmental benefits, with the current seawater mining methods posing little to no environmental hazards. Most soluble uranium is in its U(VI) oxidation state, taking the uranyl [UO2]2- configuration. This compound readily forms stable complexes with carbonate, CO32-, with the most stable complex being [UO2(CO3)3]4-. In order to make the sequestering process both economically and chemically feasible, designed molecules must form complexes that can compete with carbonate; a challenging task due to its atypical geometry. To accurately determine if our molecules can compete with this carbonate species, their binding constants must be determined and compared to the uranyl carbonate complex. We have efficiently synthesized and purified five multi-topic amidoximes that are possible contenders for uranium extraction, with synthetic and purification strategies for five more amidoximes. Utilizing UV/Vis and potentiometric titrations, we determined the binding constants of the amidoxime ligands. Successful completion of this project will produce recyclable, multi-topic amidoxime molecules for the efficient, economical, and environmentally friendly sequestering of uranium from seawater.

Category

Physical Sciences

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Apr 15th, 11:00 AM Apr 15th, 12:00 PM

Synthesis and Binding Constants for Poly-Amidoxime Uranyl Complexes for Sequestering Uranium from Seawater

In today's world the need for a constant, easily obtainable power supply is an everyday challenge. One underutilized resource that the world has is nuclear power, namely nuclear fission. Currently there is an estimated 4.5 billion metric tons of naturally solubilized, fissile uranium in seawater, reaching concentration levels close to 3.3 ppb; approximately 1000 times the current estimated amount available for terrestrial mining. This opportunity to move away from terrestrial mining presents both economic and environmental benefits, with the current seawater mining methods posing little to no environmental hazards. Most soluble uranium is in its U(VI) oxidation state, taking the uranyl [UO2]2- configuration. This compound readily forms stable complexes with carbonate, CO32-, with the most stable complex being [UO2(CO3)3]4-. In order to make the sequestering process both economically and chemically feasible, designed molecules must form complexes that can compete with carbonate; a challenging task due to its atypical geometry. To accurately determine if our molecules can compete with this carbonate species, their binding constants must be determined and compared to the uranyl carbonate complex. We have efficiently synthesized and purified five multi-topic amidoximes that are possible contenders for uranium extraction, with synthetic and purification strategies for five more amidoximes. Utilizing UV/Vis and potentiometric titrations, we determined the binding constants of the amidoxime ligands. Successful completion of this project will produce recyclable, multi-topic amidoxime molecules for the efficient, economical, and environmentally friendly sequestering of uranium from seawater.