WATER VAPOR ADSORPTION PROPERTY OF VARIOUS CLAYS AND RELATED MATERIALS FOR APPLICATIONS TO HUMIDITY SELF-CONTROL MATERIALS

Abstract

To develop a humidity self-control material in living quarters, the water vapor adsorption-desorption properties of porous clay minerals and related materials were studied. Based on Kelvin's capillary condensation theory, suitable pore diameters for the adsorption of water vapor at 0.4 and 0.7 of relative vapor pressure were calculated to be 3.2 and 7.4nm, respectively. The adsorption-desorption isotherms of sepiolite, allophane, diatomite, and selectively leached clay minerals were measured and considered as candidates for humidity self-control materials.