{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,30]],"date-time":"2026-04-30T10:54:55Z","timestamp":1777546495355,"version":"3.51.4"},"reference-count":34,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,18]],"date-time":"2020-09-18T00:00:00Z","timestamp":1600387200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia, Portugal","award":["UIDB\/QUIM\/0100\/2020"],"award-info":[{"award-number":["UIDB\/QUIM\/0100\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Ionic liquids have been suggested as new engineering fluids, namely in the area of heat transfer, as alternatives to current biphenyl and diphenyl oxide, alkylated aromatics and dimethyl polysiloxane oils, which degrade above 200 \u00b0C and pose some environmental problems. Recently, we have proposed 1-ethyl-3-methylimidazolium methanesulfonate, [C2mim][CH3SO3], as a new heat transfer fluid, because of its thermophysical and toxicological properties. However, there are some interesting points raised in this work, namely the possibility of the existence of liquid metastability below the melting point (303 K) or second order-disorder transitions (\u03bb-type) before reaching the calorimetric freezing point. This paper analyses in more detail this zone of the phase diagram of the pure fluid, by reporting accurate thermal-conductivity measurements between 278 and 355 K with an estimated uncertainty of 2% at a 95% confidence level. A new value of the melting temperature is also reported, Tmelt = 307.8 \u00b1 1 K. Results obtained support liquid metastability behaviour in the solid-phase region and permit the use of this ionic liquid at a heat transfer fluid at temperatures below its melting point. Thermal conductivity models based on Bridgman theory and estimation formulas were also used in this work, failing to predict the experimental data within its uncertainty.<\/jats:p>","DOI":"10.3390\/molecules25184290","type":"journal-article","created":{"date-parts":[[2020,9,18]],"date-time":"2020-09-18T10:22:23Z","timestamp":1600424543000},"page":"4290","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Thermal Conductivity of Metastable Ionic Liquid [C2mim][CH3SO3]"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2286-0111","authenticated-orcid":false,"given":"Daniel","family":"Lozano-Mart\u00edn","sequence":"first","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Faculdade de Ci\u00eancias, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal"},{"name":"Grupo de Termodin\u00e1mica y Calibraci\u00f3n (TERMOCAL), Research Institute on Bioeconomy, Escuela de Ingenier\u00edas Industriales, Universidad de Valladolid, Paseo del Cauce, 59, E-47011 Valladolid, Spain"}]},{"given":"Salom\u00e9","family":"In\u00eas Cardoso Vieira","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Faculdade de Ci\u00eancias, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2322-8425","authenticated-orcid":false,"given":"Xavier","family":"Paredes","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Faculdade de Ci\u00eancias, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal"}]},{"given":"Maria Jos\u00e9","family":"Vitoriano Louren\u00e7o","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Faculdade de Ci\u00eancias, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9011-5132","authenticated-orcid":false,"given":"Carlos A.","family":"Nieto de Castro","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Faculdade de Ci\u00eancias, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal"}]},{"given":"Jan V.","family":"Sengers","sequence":"additional","affiliation":[{"name":"Institute for Physical Science and Technology, University of Maryland, College Park, MD 20742, USA"}]},{"given":"Klemens","family":"Massonne","sequence":"additional","affiliation":[{"name":"BASF SE, RC\/OI\u2014M300, 67056 Ludwigshafen, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8541","DOI":"10.1021\/acs.iecr.8b00723","article-title":"[C2mim][CH3SO3]\u2014A Suitable New Heat Transfer Fluid? 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