High-temperature molten salts optimisation using mixture design for energy storage application

In this paper, the D-optimal mixture design method was used to determine the formulation of molten salts and optimise the following salt components: NaNO3 (A), KNO3 (B), LiNO3 (C), CsNO3 (D), Ca(NO3)(2) (E). The one-step method was used to synthesise 22 different combinations of a high-temperature molten salt mixture by varying molar ratios. The screening of high-temperature molten salt was based on the melting point, and the optimum eutectic salt mixture obtained from the Design of Experiment (DOE) shows the lowest melting point of 61.4 degrees C. Based on the experiments designed by Design of Experiment (DOE) software V9, a quadratic model was generated as a function of different salt components. Differential scanning calorimeter (DSC) was used to analyse the melting point of the eutectic salt mixture. Moreover, the optimum values fitted by the model was justified by using Analysis of Variance (ANOVA). The deviation between the experimental and predicted value was negligible (-0.56 %), which is in close relation with the DOE model.