n-Alkane hydroconversion on Zeogrid and colloidal ZSM-5 assembled from aluminosilicate nanoslabs of MFI framework type

Abstract

n-Alkane hydroisomerisation and hydrocracking experiments reveal that ZSM-5 materials synthesized by self-assembly of nanoslabs show different molecular shape selectivity than ZSM-5 synthesized by hydrothermal methods.

Beta-MCM-41 micro-mesoporous catalysts in the hydroisomerization of n-heptane: Definition of an indexed isomerization factor as a performance descriptor

“…Only trace amounts of n-butane was detected, which is consistent with the previous reported results [59]. This is due to the cracking of 2,2-dimethylpentane and 2,4-dimethylpentane which usually proceeds through βsession reactions, and not direct cracking of n-C7 [60][61][62][63][64][65][66], leading to the formation of iso-butane and propane.…”

Factors affecting isomer yield for n-heptane hydroisomerization over as-synthesized and dealuminated zeolite catalysts loaded with platinum

“…In a zeolite such as ZSM-5, which shows an inherent maximum isomer yield much lower than that of Y zeolite, an increase in the external surface area and decrease in the diffusion path length would result in an increase in the isomer yield. In fact, this is what was recently observed for decane hydroconversion over nanocrystalline ZSM-5 [32].…”

Molecular Simulations of Zeolites: Adsorption, Diffusion, and Shape Selectivity

“…So far these reactions have only been studied for severely diffusion limited MFI-and MEL-type zeolite crystals. Very small MFI-type crystals have become available, [523][524][525][526] that should afford redoing the experiments with minimal mass transfer limitations and establishing to what extent mass transport effects interfere with pure transition state shape selectivity. Interestingly, the explanation for the difference in product slate between MFI-and MEL-type zeolites does not necessarily involve transition state shape selectivity.…”