MSE Seminar Series: John Arnold, University of California Berkeley
Actinide Chemistry and it Role in Uranium Extraction from Seawater
Estimates of the total mass of uranium in seawater are on the order of 4.5 billion tons, one thousand times that present in terrestrial ores (the total ocean volume is approximately 1.4 x 109 km3; uranium is present at ca. 3 ppb). i Despite this abundance, there are several major impediments to using uranium from seawater as a viable economic source. First, the concentration of uranium is very low; second, there are relatively high concentrations of other ions that interfere with uranium separation; and third, the volumes involved are extremely high.
Our research is aimed at developing our fundamental understanding of how donor ligands bind to the uranyl ion, UO22+, with the longer-term goal of using this information to tackle the selective recognition of uranyl in aqueous solution. The results of these studies will impact the science and technology underlying our approaches to controlling the behavior of uranium in these systems, and will lead to a fundamental change in how scientists formulate models of bonding for uranyl.
This presentation will focus on new results in our search for new chemistry involving the actinide elements: Th, U, and Np. A specific emphasis will be placed on new chemistries aimed at selective extraction of U from seawater.