NSF Award
2102576
In this collaborative project, funded by the Chemical Structure, Dynamics & Mechanisms B (CSDM-B) Program of the Chemistry Division, Shannon Biros of the Department of Chemistry at Grand Valley State University and Eric Werner of the Departments of Chemistry, Biochemistry and Physics at the University of Tampa are developing a series of metal chelating agents for binding to f-elements, including the valuable rare earth metals. Applications in modern technologies including those associated with the development of automobile batteries, medical diagnostic agents, and advanced optical materials have increased the need for more efficient acquisition of rare earth elements from both raw material sources and recycled metal sources from consumer products. This project seeks to develop improved metal separations and extraction methods while adding to fundamental knowledge of f-element chemistry and extraction agent design. In this collaborative effort, a cadre of undergraduate students, including three community college students, will be trained in a broad range of areas including organic synthesis, inorganic coordination chemistry, luminescence, and analytical chemistry. The principal investigators will also work to develop student communication skills through internal and external conference presentations and will continue their commitment to supporting students in their labs who are from underserved populations in the sciences.<br/><br/>The f-block elements, including the rare earth metals, are critical in modern society, finding materials applications in common devices including smart phones, hybrid car batteries, and LED (light-emitting diode) lighting. Unfortunately, their purification from recycled materials and isolation from ground ores remains a significant challenge. In this collaborative project, new tripodal ligands that contain the carbamoylmethylphosphine oxide chelating group will be synthesized. These represent the next generation of compounds to be developed by the team to serve as selective lanthanide (Ln) and actinide (An) metal extraction agents for improved f-element separations. Metal-binding ability will be characterized by NMR (nuclear magnetic resonance) and IR (infra-red) spectroscopy, MS (mass spectrometry), X-ray diffraction and luminescence, and the extraction ability of each new ligand for Ln ions-- out of aqueous nitric acid solutions and into an organic solvent--will be determined. The overarching goal of the project is to enhance metal binding and selective extraction for this ligand system by making systematic changes to the ligand structure and to the extraction protocol conditions. These studies are designed to further understanding of the parameters that enable rational design of effective Ln/An extraction agents while also expanding knowledge of general f-element coordination chemistry.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
