Date: Thursday, April 19
Time: 3:40 pm - 5:00 pm
Location: 500 John D. Tickle Building
Membrane distillation (MD) is a membrane-based thermal distillation process in which a non-wetted microporous membrane is used to provide the pathway for vapor transport while preventing the salty feed solution from mixing with the distillate. It is therefore critical to prevent pore wetting in MD, as otherwise salt rejection would become unacceptably low. While MD also faces other challenges common in pressure driven membrane processes, such as membrane fouling and scaling, pore wetting is a unique challenge to MD and needs to be more thoroughly understood. In this presentation, I will first introduce a novel and powerful technique based on single-frequency impedance for monitoring dynamic pore wetting even before any pore has been fully wicked through. I will then discuss the fundamental mechanism of pore wetting in MD and compare pore wetting induced by two very different wetting agents: alcohol vs. surfactants. A theoretical framework that quantifies the kinetics of surfactant-induced pore wetting will be introduced. Finally, I will discuss material-based solution for overcoming the problem of pore wetting in MD.
Shihong Lin is an assistant professor in the Department of Civil and Environmental Engineering and the Department of Chemical and Biomolecular Engineering at Vanderbilt University. Lin received his Ph.D. (2012) in environmental engineering from Duke University where, under the direction of Prof. Mark Wiesner, he worked on elucidating the fundamental aspects of colloidal interaction between nanoparticles and environmental surfaces. Before joining Vanderbilt, Lin worked as a postdoctoral fellow in Prof. Menachem Elimelech’s research group at Yale University, with his research effort focused on membrane system at the water-energy nexus. Lin obtained his B.S. (2006), also in environmental engineering, from Harbin Institute of Technology, China. His current research interests include environmental applications of interfacial materials with special wetting properties, environmental interfacial phenomena, and desalination and water purification technologies at the water-energy nexus. Lin has published 46 peer-reviewed papers in leading journals in environmental science and engineering, 21 of which were published since he joined Vanderbilt. Major awards Lin has received include ACS Environmental Chemistry Graduate Student Award (2012), ACS-PRF Doctoral New Investigator Award (2016), ORAU Ralph Powe Junior Faculty Enhancement Award (2016). He was also invited to the 2016 Frontiers of Engineering Symposium by the National Academy of Engineering.