Reactivity Improvement of Magnesium Chloride by Ammonia Pre-coordination for Thermochemical Energy Storage at Approximately 100°C

Thermochemical energy storage (TcES) is a promising technology for advanced storage. This study investigated the reaction of magnesium chloride (MgCl2) and ammonia (NH3) as TcES material at approximately 100°C. Activation through NH3 absorption desorption was confirmed to increase MgCl2 surface area from 2.60 73.3 m2 g−1 create mesopores. Superior reactivity demonstrated with maximum rate 0.019 molNH3 molMgCl2−1 s−1 100°C under 100 kPa NH3, compared nonactivated pure material. In cyclic experiment 100°C, activated sample achieved high densities thermal output/storage rates 1720 kJ kgMg(NH3)2Cl2−1, 9.6 3.3 kW kgMg(NH3)2Cl2−1 on 15th cycle. Using chemical heat pump (CHP), density over 1600 achieved, demonstrating enough potential CHP utilization transformation 90–120°C.