The activity of the present three-year period concerns the development of high energy density materials for thermochemical storage. Based on the experience gained in the experimental activity of the previous three-year period, it was decided to work on the best tested materials based on magnesium sulfate supported on alumina, whose porosity will be optimised in order to guarantee both high salt loads (high energy density) and good diffusion of the gaseous reagent (high reaction/diffusion rates). The developed materials will be tested in a new test station that will allow them to be characterised in real operating conditions and the operating conditions for optimum dehydration/hydration processes to be identified, so as to exploit the full potential of these materials.

The new test station that is the subject of this report was designed and its realisation was started during the reference period. It is a compact plant, assembled on a skid with wheels, and makes it possible to use three types of reactors, depending on the load of sorbent that is to be used for the thermal storage tests. A screening reactor with 20-40 g of sorbent will be used for the first tests on the materials, in order to identify the one that guarantees the best performance with respect with the increase in temperature that occurs in the dehydration phase and the quantity of heat stored or released. A small reactor (600 g) and a large one (6 kg) which will be used to carry out demonstration-scale tests of the best-performing material, so as to fine-tune the dehydration-hydration process by identifying the optimal working conditions. The plant, managed by a control system, will be able to operate safely both in manual and automatic mode.