(86f) Study on the Mechanism of Alcohol Ether System Separation By Ionic Liquids Based on Density Functional Theory

In the process of alcohol esterification, azeotropes containing ether are often produced. The efficient separation of azeotropes containing ether has an important impact on the esterification reaction. At present, the function and characteristics of ionic liquids (ILs) in the liquid-liquid extra of ether containing systems are not clear. The interaction between ILs and alcohol ether system is calculated by quantum chemistry, and the electrostatic interaction and Van der Waals force are quantitatively analyzed based on the energy decomposition of molecular position. The orbital interaction between fragments is used to deeply analyze the essence of chemical bond, and the orbital interaction between monomers is deeply understood in the weak interaction system. On this basis, the electron density difference is used to study the change of electron density in the extraction process, so as to further explore the essence of the extraction process. The study of microextraction mechanism made it clear that ILs increased the interaction between alcohols, and determined that the extraction process was mainly affected by anions, which provided theoretical guidance for the selection of the best ILs. Then, the methanol removal performance of the best extractant is further evaluated by liquid-liquid extraction experiment and process simulation. The consistency between simulation results and experimental results shows that this method is a very useful tool and can provide theoretical guidance for industrialization.