Characterization of silica gel-water vapor adsorption and its measurement facility

Abstract

A new methodology for developing adsorption measurement facility is proposed using a Thermogravimetric Assembly. This adsorption measurement facility can meet the requirements of the adsorption experiment with a condensable reaction gas such as water vapour. Adsorption characteristics of water vapor on silica gel were analyzed and compared with those obtained with other systems. A comparison is made between the experimental isotherms with those obtained with the other system. From kinetic analysis of vapor uptake, the average effective diffusivities of water vapor by silica gel have been determined. Based on the effective diffusivity, an effective temperature, which accounts for real behavior of adsorption in the linear driving force model has been proposed. This new correlation is found to fit the experimental data across a full range of vapor temperature, for which the experiments were conducted.