Survey Summary on Salts Hydrates and Composites Used in Thermochemical Sorption Heat Storage: A Review

To improve the proficiency of energy systems in addition to increasing usage renewable energies, thermal storage (TES) is a strategic path. The present literature review reports an overview recent advancements utilization salt hydrates (single or binary mixtures) and composites as sorbents for sorption heat storage. Starting by introducing various systems, operating concept adsorption TES was clarified contrasted other technologies. Consequently, deep examination crucial problems related different types adsorbents were performed. Recent advances composite materials used also reviewed compared. A discussion safety, price, availability, hydrothermal stability issues reported. Salt display high theoretical densities, which are promising TES. However, they show number drawbacks use basic state including low temperature overhydration deliquescence (e.g., MgCl2), degradation, sluggish kinetics leading rise MgSO4), corrosiveness toxicity Na2S), mass transport due material macrostructure. biggest advantage that more hydrothermally stable. since most common phenomenon, such have lower content. Furthermore, when compared hydrates, higher prices per mass, reduces their appeal even further combined with densities. Economies scale optimization manufacturing processes may help cut costs. Among zeolites, Zeolite 13X among promising. Temperature lifts 35–45 °C reached lab-scale reactors micro-scale experiments under device settings. Although key disadvantage excessively desorption temperature, problematic attain using sources, instance, solar collectors. increase densities enhance adsorbents, been examined ameliorate achieve suitable Based on materials, MgSO4 has identified salt; it presents density salts can be impregnated porous matrix prepare order overcome connected its pure salt. pore volume reduction, potential leakage from well still exist. In addition, kinetics, stability, density, deposited suitable. Nevertheless, this solution should take into account deliquescence, cost selected salts. Therefore, design innovative predetermined properties adapted particular cycles. Finally, working condition, costs, lifetime, reparation, others, essential point commercial competitiveness. High costs temperatures, normal conditions, decrease market attractiveness. As result, introduction performance metrics within scientific community economic features suggested.