High-temperature stability of nitrate/nitrite molten salt mixtures under different atmospheres

Carolina Villada, Alexander Bonk, Thomas Bauer () and Francisco Bolívar

Applied Energy, 2018, vol. 226, issue C, 107-115

Abstract: Molten salts are widely used as thermal energy storage media in the Concentrating Solar Power (CSP) technologies. The melting point and the thermal stability of the salt determine the applicable temperature range of the storage system. The focus of this paper is to evaluate the effect of different gas atmospheres on the thermal stability of binary Solar Salt and two ternary salt mixtures containing lithium nitrate (Lithium mixture) and sodium nitrite (Hitec). The isothermal stability experiments were carried out at 550 °C during 500 h and the results show that the initial decomposition reaction of nitrate to nitrite depends strongly on the gas atmosphere. It is observed that changes in the nitrate-nitrite-ratio are the key parameters influencing the melting temperatures of the salt mixtures. For example, for experiments with oxygen in the atmosphere a large increase of the liquidus temperature of the Hitec mixture was observed. Metal oxides are formed during the irreversible decomposition of nitrite-ions but are found to affect the solidus and liquidus temperature of the salt mixtures only marginally. No carbonate formation was detected according to titration analysis of the salt mixtures in our experiments due to the absence of carbon dioxide in the atmosphere.

Keywords: Thermal energy storage (TES); Concentrating solar power (CSP); Heat transfer fluid; Nitrite formation; Oxide formation; Thermal decomposition (search for similar items in EconPapers)
Date: 2018
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (8)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0306261918308183
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:appene:v:226:y:2018:i:c:p:107-115

Ordering information: This journal article can be ordered from
http://www.elsevier.com/wps/find/journaldescription.cws_home/405891/bibliographic
http://www.elsevier. ... 405891/bibliographic

DOI: 10.1016/j.apenergy.2018.05.101

Access Statistics for this article

Applied Energy is currently edited by J. Yan

More articles in Applied Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().