Bimetallic Zero Valent Iron-Carbon Composites for In Situ Remediation

The increasing use and reuse of our limited water resources necessarily means that water contaminants will continue to be identified and will continue to accumulate in our water sources. While technologies exist to address water contaminants, we will continue to need improvements and advancements in treatment technology to better address a wide variety of water contaminants, from organic chemicals, pharmaceuticals, and personal care products, to heavy metals, pesticides/herbicides, and other toxic compounds. One opportunity that we see is to develop catalyst materials that can cost-effectively address a range of water contaminants and that can be integrated into current water treatment processes as a reactive degradation step. Iron-based nanoparticles have been extensively investigated at the laboratory bench-scale as a potential materials for reactive water treatment applications, and contaminant studies have thoroughly demonstrated that iron nanoparticles can remove contaminants through a combination of adsorption and reactive degradation. Yet iron nanoparticles remain limited to bench-scale demonstrations and some short-term in situ groundwater treatment studies. Iron nanoparticles are limited in their application due to three primary challenges: uncontrolled reactivity (and resulting short lifetime), oxidation and precipitation as iron oxides (with a loss in reactivity), and uncontrolled agglomeration and transport/immobilization in specific systems. Thus, there are critical and important engineering challenges that must be solved to enable iron-based reactive nanoparticles to eventually be used as a wide-spread water treatment technology. Further, opportunities exist to creatively design iron-based nanoparticles for specific contaminant and technology implementation scenarios.

Funded Projects:

SBIR Phase I & II with startup partner AxNano, LLC

Nanocomposite Chitosan-Graphene Oxide Membrane for Water Filtration

Here, we focus on understanding the anti-microbial properties of CSGO membranes.  This work is in collaboration with startup CatalyzeH2O, LLC, through a National Science Foundation Phase I SBIR award.  Additional goals of the project are to improve membrane stability and flux performance.

NSF Award #: 1913598

Membrane Filtration to Recover Nutrients from Wastewaters

Electrochemical struvite recovery benefits from elevated concentrations of ammonium and phosphate, as shown in our magnesium corrosion results (left). In this project, we are evaluating the performance of commercially-available polymeric membranes for the purpose of recovering ammonium and phosphate from relevant industrial wastewaters.  We will also be looking at novel membrane designs for the purpose of nutrient recovery, and we will be coordinating with our electrochemical engineering work on magnesium-electrode-driven nutrient recovery.  This project will include an economic and life cycle analysis of the proposed membranes and nutrient recovery process.

Collaborators: Prof. Greg Thoma

Photocatalytic Deactivation of Harmful Algal Blooms and Cyanotoxins

In this project, we are focused on photocatalytic degradation of cyanotoxins, such as microcystin-LR, along with deactivation and removal of the cyanobacteria that cause harmful algal blooms.  We are working to develop an immobilized nanoparticle composite approach that would allow in situ treatment of HABs and their associated cyanotoxins directly at the point source surface water, rather than relay on the need for pump-and-treatment of the contaminated water.  Results suggest that the cyanobacteria and toxins are removed simultaneously through a dual coagulation-degradation mechanism.

With collaborator Prof. Wen Zhang