Characterization of silica-PEG-CaCl2 composite sorbents in an open thermochemical heat storage reactor

Composite sorbents based on silica, polyethylene glycol (PEG) and containing calcium chloride were successfully synthetized using the sol-gel method. Their heat storage performance was investigated in a lab-scale open fixed-bed reactor. The silica/PEG matrix managed to stabilize hydrated when salt content equal 32 wt% despite partial deliquescence. presence of crystallized phase CaCl2/PEG resulting from complexation by polymer may indeed prevent leakage, which observed only increased 42 wt%. Comparative experiments with PEG-free control sample confirmed that enhances material stability. With regeneration temperature 130 °C, best performing composite sorbent exhibited an average water sorption capacity 0.37 gH2O g−1 dehydrated energy density 782 kJ kg−1 over four successive cycles at 30 °C % relative humidity. dispersion accessibility enhanced after its first dissolution Compared zeolite 13X, kinetics is much slower, halved generated power. Still, mass 70 higher than zeolite, makes it promising for applications moderate required power outputs.