Screening of Green and Environmentally Friendly Deep Eutectic Solvents and Study on Molecular Mechanism and Process for Separation of Isopropanol and Cyclohexane

As industrial development and the global economy grow rapidly, the consumption of resources and environmental pollution have increasingly intensified, making sustainable development an urgent necessity. This paper develops three types of low-toxicity, high-efficiency deep eutectic solvents (DESs) for the separation of isopropanol and cyclohexane. By screening and optimizing various hydrogen bond acceptors and donors, a variety of DES combinations were formed, and their performance was evaluated using the COSMO-RS model, thereby selecting solvents with significant separation effects. This study not only delved into the extraction mechanisms of these DESs through molecular dynamics simulations but also verified their practical application potential through liquid–liquid extraction experiments and quantum chemical analysis. Combining experimental data, the non-random two-liquid thermodynamic model was used to fit binary interaction parameters. An integrated liquid–liquid extraction-distillation process was established in Aspen V11, aimed at reducing the costs and harmful gas emissions of processes. Compared to conventional extractive distillation (ED) processes, this process saves nearly a quarter of the economic costs and reduces harmful gas emissions, demonstrating its tremendous potential for improving industrial production efficiency and promoting sustainable development.