Medium-pore (diameter ~ 6A) zeolites such as ZSM-5 and silicalite impregnated with Group VIII metals provide selective catalytic pathways for the conversion of synthesis gas to gasoline or olefins. Mössbauer and magnetic studies on these catalysts containing iron or iron plus cobalt are reported. The zeolites were impregnated with metal nitrate solutions, reduced, and carbided to yield showed F...

Ordered mesoporous SBA-15 analogs with different Si/Al ratios were successfully prepared in a two-step process from self-assembly of ZSM-5 nanoseeds at high temperature in mildly acidic media (473 K, pH 3.5). The obtained products were characterized as SAXS, XRD, N₂ sorption, FTIR, TEM, NH₃-TPD, AAS and ICP. The results show that the initial Si/Al molar ratio of ZSM-5 precursors strongly affect...

Visualizing proton-transfer processes at the nanoscale is essential for understanding the reactivity of zeolite-based catalyst materials. In this work, the Brønsted-acid-catalyzed oligomerization of styrene derivatives was used for the first time as a single molecule probe reaction to study the reactivity of individual zeolite H-ZSM-5 crystals in different zeolite framework, reactant and solven...

One-dimensional medium-pore zeolites are promising catalysts for propylene production from naphtha cracking due to their high selectivity. However, fast deactivation pore mouth blockage is preventing these being widely used in commercial applications. In this study, we molecular dynamics simulations investigate the diffusion of three one-dimensional aluminosilicate frameworks (ZSM-23, ZSM-22, Z...

The characterization and catalytic performance of Zn/ZSM-5 Zn-B/ZSM-5 catalysts in the n-hexane aromatization was reported. Catalysts were prepared by post-synthesis ion exchange thoroughly characterized means XRD, Py-FTIR, N2 adsorption, 27Al 11B MAS NMR spectroscopy electron microscopy techniques. incorporation zinc reduces Brønsted acid site density increases Lewis acidic sites final ZSM-5 b...

Two infrared OH stretching bands are produced after interaction of CO with H-ZSM-5 bridging hydroxyls. These two bands are not due to heterogeneity of the acid sites but arise from Fermi-resonance.

In the present work, two sets of Co/ZSM-5 mesoporous catalysts with different acidity and Co loadings varying from 1 to 5 10 wt% were prepared using ZSM-5-A (Si/Al = 50) ZSM-5-B 150) as support. X-ray diffraction (XRD) analysis showed that Co3O4 phase was formed in surface reducibility nanoparticles on greater comparison solid. situ FTIR pyridine adsorption characterization confirmed all contai...