Characterization and Heat Transfer Performance of Quarternary Nitrate Based Molten Salts

Abstract

The use of molten salts as heat transfer has become the preferable composition. It has excellent properties such as low melting points, high heat capacity, and a wide range of temperatures. This paper focuses on the characterization and heat transfer performance of quaternary nitrate based on molten salts whose composition has been reported by previous researchers. The quaternary molten salts (LiNO₃, NaNO₃, KNO₃, Ca(NO₃)₂) were characterized to determine the melting point and heat capacity using Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC), respectively. The heat transfer performance was then tested on the test rig of the designated system to determine the heat transfer properties of molten salts. The composition of 10 wt% LiNO3, 10 wt% NaNO₃, 40 wt% KNO₃, 40 wt% Ca(NO₃)₂ has a low melting point of 97.7°C, high heat capacity which was 0.46J/g°C, and maximum thermal stability temperature was 439.04°C. The heat transfer performance test showed that this sample can be used as heat transfer fluid and can store energy in the system. In conclusion, quaternary nitrate-based molten salt is a promising candidate for heat transfer and energy storage in heat recovery applications.