Converting Nitrogenous Wastes to Valuable Products
Water and wastewater treatment ideology is moving toward reclaiming contaminants and waste products as a valuable resource rather than simply something that requires removal. Because of the ubiquitous nature of the nitrogen cycle (e.g., fertilizer), many problematic compounds found in drinking water sources, wastewater, and air are nitrogen based including nitrate, nitrous oxide, and urea. Typically, these compounds are converted into dinitrogen, an innocuous by-product, but there exists a need to develop new methods for creating valuable nitrogen by-products. As such, the objective of this research area is to develop a fundamental understanding of the conversion of select nitrogenous contaminants and use those outcomes to design new materials.
Fate of Nanomaterials with Complex Surfaces
Engineered nanomaterials (ENM) are becoming commonplace in consumer products (e.g., clothing, electronics, food, packaging), and they will be released into the environment at some point in their life cycle (i.e., manufacturing to end-of-life). Understanding the transport behavior is essential to determining ENM risk to the environmental and human health. Though ENMs begin as simple, pristine particles, their surface obtains varying degrees of complexity as they interact with new surroundings, such as polymers from plastics or macromolecules present in streams. We have identified the understanding this complexity as a significant need in the field, thus resulting in three projects for this research area: (i) The dynamic interaction between macromolecules and ENMs in the aquatic environment, (ii) Coupling laboratory experiments, field experiments, and modeling to determine the fate of complex ENMs in complex streams, and (iii) Correlating macromolecular coatings on ENMs and bioactivity.
Real-time Investigation of the Solid-Liquid Interface
Nanomaterials are small particles (typically less than 100 nm) that have unique physico-chemical properties, including surface chemistry. In aquatic systems, we can get a robust understanding of nanomaterial surface chemistry by studying the solid-liquid interface. For this research area, we are using a unique molecular-scale analytical technique, time-resolved in-situ attenuated total reflectance Fourier transform infrared (TRIS-ATR-FTIR) spectroscopy, to determine mechanisms of the dynamic interactions that occur at the solid-liquid interface of the ENM.