Document type
Conference papers
Document subtype
Abstract
Title
Molten Salts and Ionic Liquids for Heat Transfer and Storage. A Digression for Sustainability
Participants in the publication
Maria José V. Lourenço (Author)
Dep. Química e Bioquímica
CQE
Carlos Nieto de Castro (Author)
Dep. Química e Bioquímica
CQE
Fernando J.V. Santos (Author)
Dep. Química e Bioquímica
CQE
Manuel M. Lopes (Author)
Dep. Química e Bioquímica
Valentim Nunes (Author)
INSTITUTO POLITÉCNICO DE TOMAR
Summary
Molten salts have been used in the past for high temperature applications, like catalytic medium for coal gasification, molten salt oxidation of wastes, latent or sensible heat storage in solar energy applications or nuclear power station operations. They are also excellent for heat transfer applications, namely in concentrated solar power (CSP) technologies, because of their impact on energy efficiency, namely in energy savings and decrease of carbon footprint. These kind of technologies operate in ranges of temperature for which molten salts are particularly adequate, due to its main characteristics: stability at high temperatures, low vapor pressure, liquid state in a large range of temperatures, ability to dissolve many inorganic and organic compounds, viscosity generally low (as ions are mutually independent) and high heat capacity per unit volume [1].\nIonic liquids, having a similar plethora of properties, are more convenient applicable to lower and medium range temperatures, mostly because when mass flow is important, they usually have higher viscosities and can degrade at temperatures above 250ºC. Industrial utilization of ionic liquids depends on the cost/kg of its production, still presently high [2].\nThe new trends for the evolution of our society and namely our economy, require that future industrial and domestic uses sustainable chemicals, free of environment and human risks, but necessarily efficient in heat transfer and storage. And here, it is understood that the future chemical industry should be mostly driven by the sun [3].\n\nThis paper presents a discussion on the possible systems to be used for heat transfer and storage, in the different temperature ranges, at low pressures, based on molten salts, ionic liquids and nanosalts, in a 2050 sun powered and sustainable society. Their use is also restricted by the availability of thermophysical property data, necessary to obtain an optimal equipment’s design, which quality is, in many cases, non-adequate [1,2]. \nThe new trends for the evolution of our society and namely our economy, require that future industrial and domestic uses sustainable chemicals, free of environment and human risks, but necessarily efficient in heat transfer and storage. And here, it is understood that the future chemical industry should be mostly driven by the sun [3].\nREFERENCES\n\n[1] V. M. B. Nunes, M. J. V. Lourenço, F. J. V. Santos, C. A. Nieto de Castro, “Molten Alkali Carbonates as Alternative Engineering Fluids for High Temperature Applications”, Applied Energy (2019), 242, 1626–1633.\n[2] F.E.B. Bioucas, S.I.C. Vieira, M.J.V. Lourenço, F.J.V. Santos, M.L.M. Lopes, C. A. Nieto de Castro, K. Massonne, “[C2mim][CH3SO3] – A Suitable New Heat Transfer Fluid? Part 1. Thermophysical and Toxicological Properties”, Ind. Eng. Chem. Res. (2018) 57, (25), 8541-8551.\n[3] A. González-Garay, N. Mac Dowell, N. Shah, “A carbon neutral chemical industry powered by the sun”, Discover Chemical Engineering (2021), 1, 2\n
Editor(s)
Institute of Chemical Engineering Sciences
Date of Publication
2022-06-05
Institution
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Event
28th EUCHEM Conference on Molten Salts and Ionic Liquids
Publication Identifiers
Address
Patras, Greece
Organizers
Institute of Chemical Engineering Sciences