Yi. Aristov et al., SELECTIVE WATER SORBENTS FOR MULTIPLE APPLICATIONS .1. CACL2 CONFINEDIN MESOPORES OF SILICA-GEL - SORPTION PROPERTIES, Reaction kinetics and catalysis letters, 59(2), 1996, pp. 325-333
This paper presents sorption properties of a selective water sorbent b
ased on mesoporous KSKG silica gel as a host matrix and calcium chlori
de as a hygroscopic salt. Sorption isobars, isochores and isotherms at
T = 20 - 150 degrees C and vapor partial pressures of 8 - 133 mbar cl
early showed two types of water sorption: 1) the formation of solid cr
ystal hydrates at low amounts N of sorbed water, and 2) vapor absorpti
on mainly by the salt solution at higher N. Sorption properties of CaC
l2 crystal hydrates were found to change strongly due to their impregn
ation into mesoporous silica gel, whereas the solution confinement to
the mesopores did not change its water sorption properties with respec
t to the bulk solution Isosteric sorption heat was measured to depend
on water sorption and to change from 62.5 kJ/mol for solid hydrates to
42.2 - 45.6 kJ/mol for solution.