Volume 22: Sustainable Energy Solutions for a Post-COVID Recovery towards a Better Future: Part V

Energy storage materials MgO-Hitec molten salt composite by electromagnetic heating In-situ preparation Jinling Hu, Xiaolan Wei， Jing Ding ， Weilong Wang， Jianfeng Lu， Shule Liu

Abstract

Molten salt can be effectively improved its specific heat capacity doped with nanoparticles.In this paper,the influence of different contents of MgO on the specific heat capacity of Hitec(KNO3-NaNO2-NaNO3) is investigated. MgO-Hitec is synthesized with electromagnetic by heating to rapidly increase the temperature of the nucleation method, MgCl2·6H2O as the magnesium source.The specific heat capacity of the composite molten salt fluid was measured with a differential scanning calorimeter (DSC). X-ray diffraction (XRD), nanoparticle size analyzer and scanning electron microscope (SEM) were used to characterize the MgO-Hitec molten salt synthesized in situ. The results show that the specific heat capacity of 2.5% MgO-Hitec fluid is 1.737 J∙g-1∙K-1, which is 23% higher than the 1.429 J∙g-1∙K-1 of Hitec-based salt. The average grain size of the synthesized MgO is ~40nm, the average particle size is less than 250nm, and there is a certain degree of aggregation of MgO in the newly synthesized composite salt. The heat storage density is the largest up to 9.87×105 kJ∙m-3. The composite molten salt is suitable for solar energy transfer and heat storage materials.

Keywords In-situ synthesis; MgO-Hitec composite molten salt; heat storage