Sr(NH3)8Cl2-Expanded Natural Graphite composite for thermochemical heat storage applications studied by in-situ neutron imaging

This work presents an in-situ neutron imaging study of the ammonia sorption reaction in a SrCl2-Expanded Natural Graphite (ENG) composite loaded into honeycomb-shaped stainless-steel scaffold and enclosed thermochemical heat storage (THS) reactor prototype. The performance SrCl2/Sr(NH3)8Cl2-ENG under different pressures temperatures was investigated spatio-temporal content calculated from radiograms. Quantitative image analysis revealed formation Sr(NH3)8Cl2 upon uptake, while desorption studies partial resulting monoamine phase Sr(NH3)Cl2 via stepwise release ammonia. Neutron also allowed indirect evaluation honeycomb conductivity showed that is transferred prevalently ENG matrix. Finally, tomography prototype performed to ensure stability THS system material throughout cycling experiments.