Effect of the Acid Properties on the Diffusion of C7 Hydrocarbons in UL-ZSM-5 Materials

1. Introduction Mesoporous UL-ZSM-5 materials have zeolitic structure in the form of nano-particles inter-grown in the walls of the amorphous wormhole-like aluminosilicate mesoporous precursor, and were shown to exhibit an intermediate acidity between the parent mesoporous precursor and ZSM-5 zeolite [1,2]. These materials combine the advantages of both, i.e., microporous crystalline zeolites (strong acidity and good thermal/hydrothermal stability), and mesoporous materials, e.g., highly ordered large pores and high specific surface areas. They have been considered to have a great potential for applications in catalysis and adsorption technologies, particularly as acid catalysts for bulky hydrocarbons conversion [3].