(2mi) Advancing Switchable Solvents for the Sustainable Water Reuse and Desalination Applications

Research Interests: Switchable solvents offer a radically new approach to water reuse and desalination processes. When mixed with an aqueous solution, the solvents exhibit certain properties, such as hydrophilicity, that can allow them to extract water, metal ion contaminants, or a variety of other target molecules. The application of an external stimulus, such as low-grade heat or CO₂, reversibly switches the solvent to its opposite state, at which the separated substance can be recovered. The switchable solvent is regenerated for reuse, reducing the overall environmental impact of the separation process. To advance this technology towards implementation, however, further studies are needed to shed light on the mechanisms driving solvent loss from kinetics, thermodynamics, and structure-property-performance perspectives. Furthermore, while solvents with switchable hydrophilicity have been studied for desalination operations, they have not been assessed for targeted removal of emerging organic contaminants, such as pharmaceuticals and pesticides. My research interests aim to deepen our fundamental understanding of switchable solvents and extend their applications to emerging water treatment needs.

Doctoral Research: My doctoral research has focused on the application of switchable solvents for the management of hypersaline brines, which are of growing environmental importance but presently underserved by conventional treatment methods. Temperature swing solvent extraction (TSSE) is an emerging technology that is able to desalinate these brines, thereby reducing their volume and facilitating disposal while simultaneously producing fit-for-purpose water to alleviate supply stress. TSSE utilizes a switchable solvent with thermally responsive polarity to extract water from the hypersaline brine while rejecting salts. Low-temperature heat triggers the solvent to switch from a hydrophilic to a more hydrophobic state, causing the product water to disengage from the extract and regenerating the solvent to be recycled into the process. My doctoral research advances our understanding of TSSE along four main dimensions: (a) investigating the influence of temperature on equilibrium partitioning of water, salt, and solvent, (b) conducting Hunter-Nash analysis of ternary diagrams to design an intermediate-step separation process that dramatically improves salt rejection while maintaining high water recovery yields, (c) formulating a thermodynamically rigorous physical chemistry framework for a priori determination of ion activity coefficients in TSSE multicomponent biphasic systems, and (d) assessing key physicochemical properties that determine the fate of organic contaminants found in real hypersaline brines.

Teaching Interests: My undergraduate degree is in Chemical Engineering and my Ph.D. is in Environmental Engineering. I feel qualified and motivated to teach core undergraduate courses such as thermodynamics, separation fundamentals, and aquatic chemistry. In addition, I can design graduate-level courses on physicochemical processes for water treatment as well as advanced thermodynamics with an emphasis on activity coefficient modeling. I have been a teaching assistant for a highly technical Aquatic Chemistry course as well as a broader Alternative Energy Resources course. In addition, I have mentored several undergraduate students, from diverse and underrepresented backgrounds, within the Yip research lab. I was awarded the distinction as my department’s 2023–2023 Lead Teaching Fellow and am on track to complete the Teaching Development Program at Columbia University’s Center for Teaching and Learning.