Adsorption equilibrium and kinetics of toluene on hierarchical mordenite

The adsorption isotherms and kinetic curves of toluene on a series of hierarchical mordenite zeolites with different mesoporosities were measured to investigate the effect of hierarchical pore structures of mordenite on the adsorption and kinetics. The isotherms of hierarchical mordenites show the combination of characteristics of both micropore and mesopore adsorption. Furthermore, the fitting of experimental isothermal data of toluene reveals that the isotherms of toluene can be well described by dual-sites Toth-type model. The fitting parameters and the Henry's constants (K_H) and the initial heats of adsorption (Q_st) calculated show that the introduction of mesopores into mordenite weakens the interaction between toluene and zeolitic surface. Additionally, the adsorption kinetic curves show that the adsorption rates of toluene on hierarchical mordenite are much larger than that on microporous mordenite, revealing the enhanced effect of mesopore on the mass transfer in zeolites.