Comprehensive evaluation of the role of phenolate based ionic liquid on extracting pyrrole from diverse sources: A combined molecular dynamics simulation study and experiment validation

Abstract

Ionic liquids have acted as a hopeful solvent in separation field over the past decade due to its functional groups contributed in separation process. Thus, to test the effect of the phenolate anion on extracting typical heterocyclic N-compound, pyrrole was selected as the representative compounds due to its high content from diverse sources. In this work, the simple structure and easy prepared functional phenolate-based ionic liquid, 1-ethyl-3-methylimidazolium phenolate ([emim][Phe]), is evaluated to separate pyrrole with the polarity analysis by COSMO-SAC model. After understanding the H-bond donor or acceptor relationship of the studied regents, the interaction mechanism between the phenolate based ionic liquid extractant itself and its complex system with pyrrole are visual demonstrated by the RDF, SDF plots etc. analysis and experimental research, which can contribute to understand the H-bonds interaction, hydrogen atom connected to the heteroatoms in pyrrole and oxygen atom in phenolate anion, more indicative. Additionally, the liquid–liquid phase behavior of the methylbenzene + pyrrole + [emim][Phe] system was determined to verify the effect at the perspective of phase equilibrium, the values of D and S was calculated and a highly selectivity for pyrrole could be confirmed. This will lay a solid foundation for developing a new separation technology about the extraction of heterocyclic N-compounds such as pyrrole.