The actual adsorption structures of non-aromatic hydrocarbons on the MFI-type zeolites have not yet been determined. This is due to the presence of twinning, which makes crystallographic analysis difficult. We recently overcame this problem, and now report the various adsorption structures of n-butane, n-pentane, n-hexane, 1-butene, cis and trans-2-butene, 2-butyne and isopentane on silicalite-...

Precession electron diffraction (PED) is a method that considerably reduces dynamical effects in electron diffraction data, potentially enabling more straightforward solution of structures using the transmission electron microscope. This study focuses upon the characterization of PED data in an effort to improve the understanding of how experimental parameters affect it in order to predict favo...

It is important to elucidate the role of surface areas and pore volumes hierarchical zeolites understand their behavior as catalysts. Micro-and mesopore MFI (Mobil Five zeolites) were assessed following several methods: (i) N2 adsorption at 77 K using classical corrected t-plot analyses methods, (ii) pre-adsorption n-nonane was followed by study K, (iii) non-local-density functional theory (NLD...

We have explored mechanically embedded three-layer QM/QM/MM ONIOM models for computational studies of binding in Al-substituted zeolites. In all the models considered, the high-level-theory layer consists of the adsorbate molecule and of the framework atoms within the first two coordination spheres of the Al atom and is treated at the M06-2X/6-311G(2df,p) level. For simplicity, flexibility and ...

Quasielastic Neutron Scattering (QENS) was employed in order to probe the dynamics of water confined within copper-loaded MOR, MFI and CHA zeolite frameworks temperature range 100–300 K. At 100 K, motion outside experimental time window adsorbate appeared static. Rotational quasielastic line broadenings were observed across all three Cu-zeolites at 200 K; both rotation translation pronounced 30...

In situ IR spectroscopy was used to observe the intermediates formed on zeolites FAU and MFI during the synthesis of methyl methoxyacetate (MMAc) via carbonylation of dimethoxymethane (DMM) and the disproportionation of DMM to dimethyl ether (DME) and methyl formate (MF). Both reactions are initiated by the reaction of DMM with the Brønsted acid protons of the zeolite to form methanol and metho...

Gas separation efficiencies of three zeolite membranes (Faujasite, MFI, and Chabazite) have been examined using the method of molecular dynamics. Our investigation has allowed us to study the effects of pore size and structure, state conditions, and compositions on the permeation of two binary gas mixtures, O(2)N(2) and CO(2)N(2). We have found that for the mixture components with similar sizes...