Dr. Soryong Chae, Associate Professor in the Department of Chemical and Environmental Engineering at the University of Cincinnati, completed an Ohio Water Resources Center funded project on per- and poly-fluoroalkyl contaminants (PFAS). These contaminants have a significant impact on drinking water quality, fish and animal habitat, human health, and ecosystem services in Ohio. The extreme environmental persistence of PFAS creates increasing difficulty for impacted water to be treated by many conventional remediation and treatment technologies. This study aimed to pioneer an innovative engineering system to achieve energy-efficient removal of PFAS from water and wastewater.  

Dr. Chae and his team focused on the incorporation of carbon nanotube (CNT) sheets onto hollow fiber membranes and the effects of Joule heating on the removal of emerging PFAS via membrane distillation (MD) from water to address the current performance and productivity of MD technology. The removal of PFAS by the electively heatable CNT (30 layers)/PVDF hollow fiber membrane was studied using a bench-scale vacuum membrane distillation (VMD) process. The CNT hollow fiber membranes with 30 CNT layers showed excellent removal (> 99.9%) of model PFAS compounds at lower concentrations in feed (1 - 10 mg/L PFOA) during 12 hr operation. However, when the VMD system was fed with 1,000 mg/L PFOA solution, PFOA concentration in the membrane permeate gradually increased, and the removal efficiency dropped below 99% after 6 hr operation.

These results provide insight into processes for the effective removal of PFAS from water and wastewater subjected to advanced treatment technologies, as well as fundamental understanding of fate and transport of PFAS through CNT layers and polymer membranes.

The USGS Groundwater and Streamflow Information Program (GWSIP) serves as the national source of impartial, timely, and rigorous data for waters across the United States. New data visualization from USGS stream gaging shows low- and high-flow events across the US during the last few months of 2022. The animation shows that while the Western U.S. and the Great Plains experienced droughts, Hurricane Nicole in Florida brought high waters to the Appalachia. Concurrently, the Northwestern U.S. experienced flooding as an atmospheric river brought excess rain. These data provide information for uses in water supply and management, monitoring floods and droughts, design of urban development, determination of flood risk and many recreational activities.