Separation of liquid mixtures is a critical step for a wide range of practical processes such as wastewater remediation, biofuel production, water purification, and contaminant removal from groundwater. Conventional separation methods, such as distillation or liquid-liquid extraction, are often limited either by their high energy consumption or their inability to separate mixtures with similar boiling points. This project aims to establish a new technological platform enabling the rational design of absorbents that can efficiently separate not only immiscible (heterogeneous mixtures such as oil and water) but also miscible liquid mixtures (homogenous mixtures such as alcohol and water). Such absorbents will surpass the technologies currently used in a variety of environmental, biomedical, and pharmaceutical applications; thus, the outcomes of this research also have the potential to advance national health and prosperity. The project will also support outreach and educational activities. Both graduate and undergraduate students’ knowledge of materials and surface science will be fostered through a curriculum that is integrated with the results of this research. Furthermore, a STEM course module for students with special needs will be developed by collaborating with the Department of Special Education at the University of Kansas.
The long-term goal of this project is to establish a fundamental understanding of interfacial interactions between solids and liquids in miscible liquid separation processes. This research will describe relationships between interfacial parameters involved in the selective absorption-driven separation processes, including absorbent–liquid intermolecular interaction, interfacial wettability, and selective absorbency. The specific research objectives are to (1) synthesize and characterize a thermo-responsive absorbent that can selectively absorb a polar liquid while repelling a non-polar liquid; (2) characterize the intermolecular interaction between absorbent and liquid based on the Flory–Huggins theory; (3) quantify the relationship between the intermolecular interaction and the absorbency; (4) establish a mathematical framework between the intermolecular interactions, interfacial wettability, and absorbency; (5) validate the proposed framework by conducting selective absorption experiments on the miscible polar–polar liquids and the spontaneous release of the absorbed liquid from the absorbent; and (6) test the possibility of a broader impact for practical applications. This project will provide fundamental understanding of the interfacial interactions taking place at the boundary between the absorbent and liquid by studying the relationships among the three critical interfacial parameters involved in the absorption-driven separation process: the intermolecular interaction, interfacial wettability, and the absorbency. The selective absorbency-driven separation of liquids will be transformative, novel, and may serve as a viable alternative to the complex, energy-intensive thermal distillation or liquid-liquid extraction methods currently in use. This project is jointly funded by the Interfacial Engineering program and the Established Program to Stimulate Competitive Research (EPSCoR).
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
