Structured filamentous zeolitic materials were synthesized by ZSM-5 coatings deposited on the glass fibrous supports. A homogeneous coverage of the support filaments was obtained via the synthesis of MFI crystals in fluoride-containing media at neutral pH ∼7. These materials combine the open macrostructure of woven filamentous fabrics with well-defined microstructure of ZSM-5 crystals. The samp...

ZSM-5 zeolites were prepared at neutral pH by fluoride-mediated synthesis. The degree of crystallinity, the specific surface area and the crystal size are higher than those of the zeolites prepared under alkaline conditions. Moreover, by varying the F/Si ratio from 0.3 to 1.6, the H–[F]–ZSM-5 zeolites with crystal size ranging from 10 to 75 lm and the specific surface areas from 60 up to 350 m/...

The direct conversion of methane and carbon dioxide to acetic acid is one of the most challenging research topics. Using the density functional theory (M06-L) the study reveals the catalytic activity of the Au(I)-ZSM-5 zeolite in this reaction. The Au(I)-ZSM-5 is represented by a 34T quantum cluster model. The activation of the C-H bond over the Au-ZSM-5 zeolite would readily take place via the...

The aim of this work was to establish the effects of zeolite structure/chemical composition on the activity and selectivity of Cu-exchanged Y (Si/Al = 2.5), ZSM-5 (Si/Al = 12), and Mordenite (Si/Al = 10) for the oxidative carbonylation of methanol to DMC. Catalysts were prepared by solid-state ion-exchange of the H-form of each zeolite with CuCl and were then characterized by FTIR and X-ray abs...

The mono(μ-oxo) dicopper cores present in the pores of Cu-ZSM-5 are active for the partial oxidation of methane to methanol. However, copper on the external surface reduces the ratio of active, selective sites to unselective sites. More efficient catalysts are obtained by controlling the copper deposition during synthesis. Herein, the external exchange sites of ZSM-5 samples were passivated by ...

The adsorption performance of Fe/ZSM-5 catalyst has been investigated in the SCR of NOx with propylene as the reducing agent. Freudlich equation was found to fit the adsorption isotherm satisfactorily if the system dispersion is considered. Fe/ZSM-5 catalyst showed reasonable NO adsorption capacity. The study on the influence of reaction temperature, gas space velocity and gas composition on th...

ZnO modified ZSM-5 and Y zeolites are synthesized by performing atomic layer deposition (ALD) of ZnO to HZSM-5 and HY using diethyl zinc and water as the precursors. The surface area and pore volume of ZSM-5 and Y zeolites are progressively reduced with the increasing number of ZnO ALD cycles. XRD and SEM characterization methods show that highly dispersed ZnO species are deposited on the inter...

Dimethyl carbonate (DMC) and dimethoxy methane (DMM) are of commercial interest because they are good fuel additives and building blocks for organic synthesis. Both products can be produced using Cu-exchanged ZSM-5 and Y from a mixture containing O2, CO, and CH3OH. Experimental studies done in our research group [1,2] have shown that at identical reaction conditions, very different product sele...