Encyclopedia of Applied Electrochemistry

2014 Edition
| Editors: Gerhard Kreysa, Ken-ichiro Ota, Robert F. Savinell

High-Temperature Molten Salts

  • Mathieu Salanne
Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-6996-5_502

Introduction

Molten salts, together with their low-temperature analogues, the room-temperature ionic liquids, constitute a particular class of electrolytes which do not contain any solvent. They are composed of inorganic ions only: The cations (Mp+) are metallic species while the anions (Xq−) can either be halides (F, Cl, Br, I) or polyatomic species (NO3 and CO32− mainly); the archetypal molten salt is sodium chloride NaCl. Being solid at ambient conditions, these salts are generally used in high-temperature applications (it is worth noting that some compounds have relatively low melting points, e.g., NaAlCl4 melts at 152 °C).

Despite the fact that the most important industrial applications of molten salts have started at the beginning of the twentieth century with the large-scale production of aluminum, their structure has long remained largely unknown. Most of the short-range structural properties can be attributed to the competition between packing effects and electrostatic...

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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Laboratoire PECSA, UMR 7195, Université Pierre et Marie CurieParisFrance