Microspectroscopic methods were explored to investigate binder effects occurring in ZSM-5-containing SiO2- and Al2O3-bound millimetre-sized extrudates. Using thiophene as a selective probe for Brønsted acidity, coupled with time-resolved in situ UV/Vis and confocal fluorescence microspectroscopy, variations in reactivity and selectivity between the two distinct binder types were established. It...

The influence of a highly oxygenated, polar protic reaction medium, that is, levulinic acid in 2-ethylhexanoic acid, on the dealumination of two zeolite-supported ruthenium catalysts, namely Ru/H-β and Ru/H-ZSM-5, has been investigated by 27 Al triple-quantum magic-angle spinning nuclear magnetic resonance spectroscopy (3QMAS NMR). Upon use of these catalysts in the hydrogenation of levulinic a...

To improve the yield of propylene in fluidized catalytic cracking, a series different Au/ZSM-5-TOS catalysts were prepared by modifying ZSM-5, using an external surface modification method and Au nanoparticles. The modified catalyst maintained MFI structure whereas pore-opening size zeolite relatively decreased, without affecting its internal structure. acidity especially Brønsted acidity, redu...

Photolysis of the supramolecular complexes (dibenzyl ketones@ZSM-5) produced supramolecular complexes of benzyl radicals@ZSM-5, which were directly detected by CW-EPR spectroscopy, and provided information on the dynamics of the radicals. The lifetimes of the radicals increased as the group X attached to the carbon atom at the radical center increases from X = H (t(1/2) ca. 2 min) to X = (CH(2)...

The structure of phenylcyclopropane radical cation (1•+, R ) H) is derived from CIDNP effects observed during the electron transfer reaction of 1 with chloranil. This species is an example of an elusive structure type. The secondary cyclopropane protons show significantly divergent hyperfine coupling constants due to an unprecedented stereoelectronic effect. Incorporation into a redox-active pe...

The acid properties of mesostructured aluminosilicates synthesized from gels precursors of colloidal ZSM-5 zeolite have been studied by FTIR spectroscopy of basic probe molecules (ammonia, CO and propene). It is shown that these materials possess stronger acid sites with higher thermal stability than those of conventional Al-MCM-41. These results explain the enhaced m-xylene isomerization activ...

this work describes the optical and structure properties of nickel sulfide and cobalt sulfide nanoparticles in zsm-5 zeolite. the samples were obtained by sulfidation of the ni2+ and co2+ ion-exchange zsm-5 zeolites in a na2s solution at room temperature. the optical properties of the samples were studied by uv-visible spectroscopy. their crystalline structure and morphology were studied by x-r...

The realization of biofuels and chemicals requires the development highly active selective catalysts, which are resistant to deactivation. A conventional ZSM-5 (SiO2/Al2O3 = 30) was modified with 0.2 M NaOH generate a mesoporous zeolite support. parent zeolite, mic-ZSM-5, hie-ZSM-5, silica support, SiO2, were impregnated 5% nickel characterized using X-ray powder diffraction (XRD), Brunauer–Emm...

Zeolites are promising materials in the field of gas sensors. In this technology-oriented paper, a planar setup for potentiometric hydrocarbon and hydrogen gas sensors using zeolites as ionic sodium conductors is presented, in which the Pt-loaded Na-ZSM-5 zeolite is applied using a thick-film technique between two interdigitated gold electrodes and one of them is selectively covered for the fir...