Development of electrospun polymer nanofiber mats for removal of uranium from aqueous systems

Abstract

Uranium contamination in drinking water sources, such as ground or surface water, poses a potential health risk. In areas, such as the Navajo Nation, uranium levels can be found at concentrations ~300 times higher than the maximum concentration limit (MCL) set by the Environmental Protection Agency (EPA) of 30 µg/L. Exposure to these contaminated waters can result in elevated uranium concentrations within the body even after several months of eliminating the source. Inside the body uranium is a nephrotoxin (damages the kidney) and has been linked to cancer among other health problems. Reducing these health risks towards individuals requires methods for cleaning uranium from aqueous systems and sensing it within water and body fluids for biomonitoring. The objective of this work was to synthesize, characterize, and test electrospun polymer nanofiber mats capable of extracting uranium from water with applications in sensing and/or point of use (POU) treatments devices. Materials were synthesized with a suite of functional groups capable of extracting uranium from aqueous systems such as amidoxime, phosphonic acids, and quaternary ammonium salts (QAS) then characterized to evaluate materials physical and chemical traits. Batch uptake studies evaluated materials uptake rates, efficiency at varying pH's, and ability to remove uranium over a range of initial concentrations. Flow through studies assessed materials abilities to be used as a POU treatment technology for removing uranium from drinking water.