The synthesis of the ZSM-5 and beta zeolites in their nanosized form has been achieved by using simple alkyl-substituted mono-cationic cyclic ammonium cations as OSDA molecules. The particular combination of a cyclic fragment and a short linear alkyl-chain group (preferentially C4) within the monocationic OSDA molecules allows directing the crystallization of nanosized zeolites with excellent s...

In this work, a systematic molecular simulation study was performed to compare the separation of CO2/N2 and CH4/N2 mixtures in two different classes of nanoporous materials, zeolites, and metal-organic frameworks (MOFs). For this purpose, three zeolites (MFI, LTA, and DDR) and seven MOFs (Cu-BTC, MIL-47 (V), IRMOF-1, IRMOF-12, IRMOF-14, IRMOF-11, and IRMOF-13) were chosen as the representatives...

DOR and MQMAS NMR techniques were applied in the high field of 17.6 T to the study of several oxygen-17 enriched zeolites with the ratio Si/Al = 1. The tendency that the isotropic chemical shift of the O NMR decreases with increasing bond angle (or s-character of the oxygen hybrid orbital) was confirmed by this study. A quite linear correlation exists for the oxygen sites in the zeolites A and ...

Molecular simulations have been used to investigate at the molecular level the suitability of zeolites with different topology on the adsorption, diffusion and separation of a nitrogen-sulfur hexafluoride mixture containing the latter at low concentration. This mixture represents the best alternative for the sulfur hexafluoride in industry since it reduces the use of this powerful greenhouse ga...

Adsorption of 1-propanethiol on Co and Cd modified, synthetic (3A, 4A and 13X) zeolites were studied by FTIR (Fourier Transform Infrared) spectroscopy and SEM-EDX (Scanning Electron Microscope-Energy Dispersive X-Ray) graphics. Amount of metal cations on mentioned zeolites was measured by AAS (Atomic Absorption Spectrometer). Based on divalent cations of zeolites, it was assumed that cations ma...

In this paper, the utilisation of zeolites synthesised from fly ash (FA) and related co-disposal filtrates as low-cost adsorbent material were investigated. When raw FA and co-disposal filtrates were subjected to alkaline hydrothermal zeolite synthesis, the zeolites faujasite, sodalite and zeolite A were formed. The synthesised zeolites were explored to establish its ability to remove lead and ...

Unique bayberry-like MFI zeolites are synthesized through a quasi-solid-state crystallization approach. This hierarchical zeolite structure has a relatively thick shell, densely grown nanocrystals with an ordered packed channel, high mechanical stability, high surface area and a low Si/Al ratio. Its catalytic efficiency for methanol-to-aromatics is significantly higher than that of conventional...

Zeolite HOU-2 (LTA type) is prepared with the highest silica content (Si/Al = 2.1) reported for Na-LTA zeolites without the use of an organic structure-directing agent. The rational design of Si-rich zeolites has the potential to improve their thermal stability for applications in catalysis, gas storage, and selective separations.

By means of an EPR investigation of Mo ions introduced into NaY zeolites by solid-state reactions, the location and coordination of Mo in zeolites were investigated. Two different locations, free and distorted tetrahedral, were found. The molecular orbital coefficient, ß, and the effective charge, Q, for the MO ions in a distorted tetrahedral structure were calculated and interpreted.