Abstract :
A family of composite sorbents was prepared by impregnating silica gel in the solution of the hygroscopic salt CaCl2 for solar heat
storage. The characteristics of water adsorbed on the composite sorbents prepared under different impregnating conditions were measured
by a micromeritics gas adsorption analyzer, a Calvet-type microcalorimeter and an open-type gravimetric method. From the results
of these dynamic sorption measurements, the effects of impregnating variables on the characteristics of water adsorbed on the composite
sorbents were evaluated. The composite sorbents prepared under different impregnating conditions were also tested on an open-type
sorption storage system. The composite sorbent prepared by impregnating in the CaCl2 solution of 30% showed a high and stable storage
capacity of 1020 J g 1 at the charging temperature of about 90 C. This study demonstrates a great potential in controlling the sorption
characteristics as well as the storage properties of the composite sorbents by optimizing the impregnating variables to meet the specific
demands of solar heat storage.
2006 Elsevier Ltd. All rights reserved.
