Angela LAMAS1, Cagenna MAGENDRAN1, Ramalianes SILVA1, Rafael ALMEIDA1, Xavier PAREDES2, Ângela F. SANTOS1, Isabel M.s. LAMPREIA1, Fernando J.v. SANTOS1, Maria José V. LOURENÇO1, Carlos A. NIETO DE CASTRO1
1Centro de Química Estrutural, Faculdade de Ciências da Universidade de Lisboa, Lisboa, Portugal
2Grupo de Termodinámica y Calibración (TERMOCAL), Research Institute on Bioeconomy, Escuela de Ingenierías Industriales, Universidad de Valladolid, Valladolid, Spain
Ionic liquid and water mixtures may show very interesting macroscopic behavior, as reflected in the change of their thermophysical properties with composition and temperature. Thermophysical properties of the binary system water and 1-ethyl-3-methylimidazolium dicyanamide, [C2mim][N(CN)2], with an assay ≥ 95%, were studied to understand the structure of the mixture and to analyze its possible use as a heat transfer fluid in industrial processes. Data obtained includes density, speed of sound, viscosity, electrical conductivity, thermal conductivity and refractive index (and derived excess properties), for all the composition range, and temperatures 293 to 343 K. Methods of measurement used were described in recent publications1-3, for [C2mim][CH3SO3] and [C2mim][CH3CO2] + water mixtures. Discussion about the structure of these mixtures will be done, based on correlation spectroscopy and computer simulations for similar mixtures of hydrophilic ionic liquids with water, like, [C2mim][C2H5SO4], [C2mim][CH3SO3], and [C4mim][BF4]3-7.
This work was supported by Fundação para a Ciência e Tecnologia, Portugal, through projects UID/QUI/00100/2013, UID/QUI/00100/2019, and UIDB/00100/2020, and by the Doctorado en Ingeniería de Procesos de Minerales, Universidad de Antofagasta, Chile, for the stay of Ms Angela Lamas in our laboratories (FONDAP/15110019).
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