Chen Liu is a third-year phd student in Dr. Kurt Pennell's group in School of Engineering at Brown University. His research interests centre on the fate and transport of Per and Polyfluorinated substances (PFAS) in subsurface system. He is also working on developing highly sorptive material to sequester mixture of PFAS and to in couple with further physicochemical and biological treatments. Chen obtained his B.A. at Wuhan University in 2013 and his M.S. at Tufts University in 2017.
STUDENT POSTER PRESENTATION
In-situ Sequestration of Perfluoroalkyl Substances (PFAS) Using Polymer-Stabilized Powdered Activated Carbon
Remediation of groundwater impacted by per- and polyfluoroalkyl substances (PFAS) is particularly challenging due to its low volatility, the strength of the carbon-fluorine bond and the extremely low drinking water health advisory levels. To address this issue, we have developed an in-situ sequestration technology that introduce polymer (PolyDADMAC) -stabilized powdered activated carbon (S-PAC) to water-saturated porous media, where the retained polymer and activated carbon serve to adsorb PFAS from contaminated groundwater. Batch reactor experiments demonstrated adsorption capacities of 322 mg/g PFOA and 316 mg/g PFOS by 100-mesh Darco® PAC. In column study with S-PAC pretreated 40-50 mesh Ottawa sand, a breakthrough time of greater than 4,000 pore volumes at an injection concentration of 50 ug/L was achieved. Subsequent aquifer cell experiments yielded similar sequestration capacities in a three-dimensional, heterogeneous domain. Therefore, the potential of polymer-stabilized activated carbon to sequester migrating PFAS is demonstrated.