Abstract
Adsorption equilibrium and effective diffusion coefficients of water vapor, in cylindrical particles of activated alumina (A) and
activated alumina impregnated with calcium chloride (MCA), are experimentally determined. The experiments were conducted at
303 K and 323 K using cylindrical particles with 2.5 mm in both length and diameter. Diffusion coefficients were determined
from the kinetics of water sorption. The measurements were conducted in a constant pressure unit based on a magnetic
suspension balance (Rubotherm) under isothermal conditions. The sorption capacity depends on temperature and it was found to
be higher by 25 % for the MCA material compared with the A material. The water diffusion coefficient depends itself on the
adsorption equilibrium taking into account the local slope of the water sorption isotherm. The effective diffusivity of water is
almost 2 times lower in impregnated than in non-impregnated alumina. The obtained diffusion data could be used to model the
dynamic adsorption.