The molecular simulation and experimental investigation of toluene and naphthalene adsorption on ordered porous silica

Abstract

In order to ensure regeneration property of adsorption materials in the air pollution purification system of the airtight cabin, such as submarine and space station, it is necessary to selectively separate semi-volatile organic compounds whose desorption is difficult. For this reason, the effects of pore size on the adsorption capacity and adsorption selectivity of toluene and naphthalene were investigated by both molecular simulation and experimental investigation. The ordered porous silica-based adsorbents with pore sizes ranging from 1.0 nm to 2.8 nm were constructed by simulation and were prepared by template synthesis method in this study. Both simulation and experiment show that the adsorption capacity of toluene and naphthalene firstly increased and then decreased with the increase of the pore size of adsorbents from 1.0 nm to 2.8 nm, and the pore diameter (1.3 nm) corresponding to the maximum adsorption amount of toluene was smaller than that (2.3 nm) of naphthalene. Simulation results show that the adsorption energy and adsorption stability of naphthalene are higher than those of toluene, and binary-component co-adsorption experiments also testified that toluene molecules could be replaced by naphthalene molecules. The optimum pore size for selective adsorption of naphthalene is 2.3 nm.