Unraveling the Diffusion Properties of Zeolite-Based Multicomponent Catalyst by Combined Gravimetric Analysis and IR Spectroscopy (AGIR)

The concept of pore hierarchization for enhancing zeolite catalytic performance has been the main focus during the past decade; the main research activities have widely emphasized the preparation of single-component hierarchical zeolite catalysts. Here we report on the critical aspect of interconnectivity of multicomponents in hierarchical zeolite catalysts using a combined gravimetric and infrared spectroscopy (AGIR) analysis. The variances of macroscopic diffusion behaviors between the global multicomponent catalyst (indexed as global diffusion time constant) and its zeolitic moiety (indexed as micropore diffusion time constant) are differentiated via simultaneous gravimetric and infrared analysis, respectively. The effectiveness factors correlated with the diffusion time constants show that the nonideal interconnectivity between the zeolitic and nonzeolitic components weakens the full potential of the multicomponent catalyst.