{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,23]],"date-time":"2026-09-23T05:04:37Z","timestamp":1790139877088,"version":"4.0.1"},"reference-count":47,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T00:00:00Z","timestamp":1789948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["22573056"],"award-info":[{"award-number":["22573056"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"crossref"}]},{"award":["22573056"],"award-info":[{"award-number":["22573056"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Natural Science Foundation of Shandong Province","award":["ZR2024QB052"],"award-info":[{"award-number":["ZR2024QB052"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Ionic liquids (ILs) have attracted significant attention as green solvents for azeotrope separation via extractive distillation; however, the microscopic mechanism by which ILs eliminate azeotropic phenomena remains inadequately understood. This study employs a combination of spectroscopic methods and theoretical calculations to elucidate the mechanism by which 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide ([BMIM][NTf2]) breaks the ethanol\u2212acetonitrile azeotrope. Analysis of the hydroxyl stretching vibration region of ethanol indicates that the ethanol\u2212acetonitrile cross-interaction is weaker than ethanol self-association, which is responsible for the minimum-boiling azeotrope. The addition of IL breaks the ethanol\u2212acetonitrile azeotrope. The underlying mechanism is that the addition of the IL induces the formation of stronger interaction complexes between ethanol and the IL, which enhances the relative volatility of the azeotropic constituents and thereby enables azeotropic separation. This work provides a critical basis for elucidating the molecular mechanism responsible for the disruption of azeotropic phenomena by ILs.<\/jats:p>","DOI":"10.3390\/molecules31183345","type":"journal-article","created":{"date-parts":[[2026,9,21]],"date-time":"2026-09-21T14:12:09Z","timestamp":1789999929000},"page":"3345","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular Mechanism of Ethanol\u2212Acetonitrile Azeotrope Disruption by the Ionic Liquid [BMIM][NTf2]"],"prefix":"10.3390","volume":"31","author":[{"given":"Pingxiao","family":"Jia","sequence":"first","affiliation":[{"name":"Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"}]},{"given":"Sainan","family":"Wen","sequence":"additional","affiliation":[{"name":"Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Xiuyu","family":"Du","sequence":"additional","affiliation":[{"name":"Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Kuan","family":"Ji","sequence":"additional","affiliation":[{"name":"Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Jiao","family":"Ma","sequence":"additional","affiliation":[{"name":"Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"data-curation","vocabulary":"credit"}]},{"given":"Yilin","family":"Lyu","sequence":"additional","affiliation":[{"name":"Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"formal-analysis","vocabulary":"credit"}]},{"given":"Yu","family":"Zhou","sequence":"additional","affiliation":[{"name":"Shandong Sino-Japanese Center for Collaborative Research of Carbon Nanomaterials, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zhong, P., Zhang, L., Luo, N., and Liu, J. 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