| Summary: | Thin-film composite (TFC) membranes, the backbone of modern reverse osmosis and nanofiltration, combine the high separation performance of a thin selective layer with the robust mechanical support. Previous studies have shown that heat released during interfacial polymerization (IP) can have a significant impact on the physical and chemical structure of the selective layer. In this study, we develop a multilayer transient
heat conduction model to analyze how the thermal properties of the materials used in
TFC fabrication impact interfacial temperature, focusing on support-free (SFIP), conventional (CIP), and interlayer-modulated IP (IMIP). Using a combination of analytic
solutions and computational models, we demonstrate that the thermal effusivities of
fluid and material layers can have a significant effect on the temporal evolution of
interfacial temperature during IP. In CIP, we show that the presence of a polymeric
support adjacent to the reaction interface yields a 20% to 60% increase in interfacial
temperature rise, lasting for ∼ 0.1 s. Furthermore, we demonstrate that inorganic or
metallic interlayers, which have high thermal effusivities, can lead to short-lived orderof-magnitude reductions in interfacial temperature rise. Finally, we provide analytical
approximations for transient heat conduction through multilayered systems, enabling
rapid evaluation of the thermal impact of novel membrane support and interlayer materials and structures on interfacial temperature during TFC fabrication. Quantifying
how the thermal properties of solvents, support layers, and interlayers affect interfacial
temperature during IP is critical for the rational design of new TFC membranes.
|
|---|