As valuable chemical materials, the heterocyclic nitrogen compounds are widely found in nature, and they are in common use. In this paper, the multiscale interaction mechanisms between 1-ethyl-3-methylimidazolium nitrate ([emim][NO₃]) and representative heterocyclic nitrogen compounds (pyrrole and indole) during the extraction process are investigated. By combining theoretical and experimental research, first, the ionic liquid and its corresponding composite systems are studied with a multiscale microscopic method. With the help of quantum chemical calculation and molecular dynamics simulation, the polarity and the difference of the interactions of [emim][NO₃] and nitrogen compounds as well as the mechanism of the separation process are explored. Additionally, the mechanism of the separation process and its effects are evaluated through phase equilibrium measurement and extraction experiment. The results reveal the highly selective separation of neutral pyrrole and indole and lay a solid foundation for the development of a new extraction process for complex systems containing neutral heterocyclic nitrogen compounds.

中文翻译：

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[emim] [NO ₃ ]作为萃取剂分离中性杂环氮化合物的多尺度探索和实验研究

作为有价值的化学材料，杂环氮化合物广泛存在于自然界中，并且它们是常用的。本文研究了1-乙基-3-甲基咪唑鎓硝酸盐（[emim] [NO ₃ ]）与代表性杂环氮化合物（吡咯和吲哚）在萃取过程中的多尺度相互作用机理。通过理论和实验研究相结合，首先，采用多尺度微观方法研究了离子液体及其相应的复合体系。借助量子化学计算和分子动力学模拟，[emim] [NO ₃ ]的极性和相互作用的差异探讨了氮化合物以及分离过程的机理。此外，通过相平衡测量和萃取实验评估了分离过程的机理及其效果。结果揭示了对中性吡咯和吲哚的高度选择性分离，为开发一种包含中性杂环氮化合物的复杂系统的新萃取工艺奠定了坚实的基础。