Binary Solid/Liquid Equilibrium of Mixtures of Thermally Robust Salts and Molecular Compounds for use as Heat Transfer Fluids

Authors

Jared Ridge Mathews, University of South AlabamaFollow

Files

Description

Fossil fuels, contributors to climate change that may bear catastrophic consequences, power the entire world. The human species is almost entirely dependent on fossil fuels for energy, but other sources of renewable and environmentally friendly energy must be developed. Concentrated solar power (CSP) is a promising source of renewable energy with hampered potential—better heat transfer fluids (HTFs) are needed for it to be economically feasible. Currently, the HTFs in industrial use are predominantly either synthetic oils or nitrate-based molten salts. Synthetic oils are only stable up to 400 °C, and molten salts often have high melting temperatures, making them prone to freezing. Therefore, ionic liquids are being investigated as an alternative heat transfer fluid. Ionic liquids often have high thermal stability, high heat capacity, and low melting points. An ionic liquid like tetraphenylphosphonium bistriflimide (TPP), combined with aromatic compounds, such as diphenyl ether, shows potential as an HTF. In this report, digital scanning calorimetry (DSC) data of binary mixtures of TPP and diphenyl ether was analyzed using binary a binary T-x plot, which was compared to an ideal eutectic model, and Tammann’s triangle, which provided a more accurate prediction of the eutectic composition, in order to make a comprehensive graph of the solid-liquid equilibrium (SLE) behavior. This data provided valuable insights into the thermodynamic properties of this mixture, including evidence about the eutectic composition and melting temperature. The eutectic composition is of special interest for its unique thermodynamic properties, including a very low melting temperature, which offers potential for use in CSP technology, significantly reducing the risk of catastrophic HTF freezing that leads to plant shutdowns and unreliability.

Publication Date

5-2025

City

Mobile

Disciplines

Biochemical and Biomolecular Engineering | Complex Fluids | Oil, Gas, and Energy | Other Chemical Engineering | Other Environmental Sciences | Sustainability

Recommended Citation

Mathews, Jared Ridge, "Binary Solid/Liquid Equilibrium of Mixtures of Thermally Robust Salts and Molecular Compounds for use as Heat Transfer Fluids" (2025). Poster Presentations. 41.
https://jagworks.southalabama.edu/honors_college_posters/41