A simple model and experiments for adsorption‐desorption hysteresis: Water vapor on silica gel

Abstract

Abstract A simple model is proposed for the evaluation of the primary and secondary adsorption and desorption processes for hysteresis‐dependent sorption systems. The model is based on the use of pore blocking interpretation of hysteresis in an interconnected network of pores. The model is simple to use and requires only the primary adsorption and primary desorption isotherms to predict all secondary desorption and adsorption isotherms. A complete set of equilibrium adsorption‐desorption curves covering the hysteresis loop (appearing in the range of relative pressure 0.3–0.7) was measured for water vapor on silica gel at 25° C. The usefulness of the model is supported by its agreement with experimental data.