The purpose of this study was to use a tape casting technique to develop an Al2O3 fiber-reinforced Al2O3-based ceramic material (Al2O3-fiber/Al2O3 composite) into a new type of dental ceramic. The Al2O3-based ceramic used a matrix consisting of 60 wt% Al2O3 powder and 40 wt% SiO2-B2O3 powder. The prepreg sheets of Al2O3-fiber/Al2O3 composite (in which uniaxially aligned Al2O3 fibers were infilt...

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...

The density functional theory (DFT) model ONIOM(M06L/6-311++G(2df,2p):UFF was employed to reveal the catalytic activity of Cu(II) in the paddle-wheel unit of the metal-organic framework (MOF)-505 material in the Mukaiyama aldol reaction compared with the activity of Cu-ZSM-5 zeolites. The aldol reaction between a silyl enol ether and formaldehyde catalyzed by the Lewis acidic site of both mater...

Formic acid oxidation reaction (FAOR) was studied using different platinum-zeolites hybrid catalysts. The catalysts were prepared by addition of two forms the ZSM-5 zeolite (ZSM-5-H+ and ZSM-5-NH4+) to an ink containing Vulcan carbon support Pt nanoparticles (NPs). TEM images demonstrate a proper mixture components in good dispersion NPs mainly over carbon. Both zeolites (ZSM-5-NH4+ ZSM-5-H+) a...