MCM-41

About: MCM-41 is a research topic. Over the lifetime, 2355 publications have been published within this topic receiving 91416 citations.

Synthesis of Novel Ag Modified MCM-41 Mesoporous Molecular Sieve and Beta Zeolite Catalysts for Ozone Decomposition at Ambient Temperature

Abstract: Mesoporous molecular sieve Na-MCM-41 with Si/Al ratio 20 and 50 and Na-beta zeolite with Si/Al ratio 11 were synthesized and characterized using X-ray powder diffraction, scanning electron microscope and nitrogen adsorption. The Ag (5 and 2 wt%) modifications of H-MCM-41-20, H-MCM-41-50 and H-beta-11 catalysts were carried out using impregnation method. The catalysts were tested in the decomposition of ozone at ambient temperature. The 5 wt% Ag-H-MCM-41 catalyst showed a very high decomposition of ozone (~98%). The 5 wt% Ag-H-MCM-41-50 catalyst exhibited higher decomposition rate than 2 wt% Ag-H-MCM-41-50. The Ag modified H-MCM-41 catalyst with higher Si/Al ratio showed higher reaction rate than the catalyst with lower Si/Al ratio. The H-MCM-41 catalyst without Ag exhibited the lowest decomposition of ozone indicating an important role of Ag in the reaction.

Gas-phase hydrogenation of acetonitrile on zirconium-doped mesoporous silica-supported nickel catalysts

Abstract: Nickel supported on zirconium-doped mesoporous silica catalysts, with varying nickel loadings (4–26 wt%), were evaluated in the gas-phase hydrogenation of acetonitrile Prior to the catalytic study, the catalysts were characterised by using XRD, XPS, HREM, H2-TPR, N2 adsorption–desorption at 77 K, H2 and O2 chemisorption and NH3-TPD The catalytic activity, at 408 K, was shown to be influenced by the incorporation procedure of nickel The catalyst prepared by ion exchange being the one which exhibits the best catalytic performance In the steady state, the turnover frequency value decreases from 0020 to 0004 mol CH3CN converted at-gNi−1 s−1 as the nickel-supported content increases from 4 to 26 wt%, but reaches the highest value (0033 mol CH3CN converted at-gNi−1 s−1) for the nickel-exchanged catalyst The selectivity, in all cases, is higher toward ethylamine (37–67 mol%), especially for higher nickel loadings The studied catalysts deactivate during the catalytic reaction, and the extent of deactivation depends on both the nickel loading and the nickel incorporation method However, the conversion and selectivity patterns of these catalysts can be completely restored after treatment with H2 at 673 K for 1 h

Direct Synthesis of MCM-41 Mesoporous Aluminosilicates Containing Au Nanoparticles in Aqueous Solution

Abstract: A mesoporous MCM-41 aluminosilicate containing Au nanoparticles catalyst of high surface area and porosity has been conveniently prepared in a simple embedding approach.