al-mcm-41 nanoreactors is found to be a remarkable efficient catalyst for one-pot multicomponent cyclocondensation of benzil, aniline or ammonium acetate and aromatic aldehydes for the synthesis of polysubstituted imidazoles under solvent-free conditions. the reaction was efficiently promoted by 10 mg nano-al-mcm-41 and the heterogeneous catalyst was recycled for four runs in this reaction with...

Ce-modified mesoporous silica materials MCM-41 and SBA-15, namely 32 wt % Ce-Si-MCM-41, 16 wt % Ce-H-MCM-41 and 20 wt % Ce-Si-SBA-15, were prepared, characterized and studied in the selective preparation of trans-carveol by α-pinene oxide isomerization. The characterizations of these catalysts were performed using scanning electron microscopy, X-ray photoelectron spectroscopy, nitrogen adsorpti...

A highly efficient heterogeneous copper-catalyzed chlorodeboronation of arylboronic acids with inexpensive N-chlorosuccinimide (NCS) was achieved in MeCN in the presence of 10 mol% of L-prolinefunctionalized MCM-41-immobilized copper(I) complex [MCM-41-L-proline-CuCl] under mild conditions, yielding a variety of aryl chlorides in excellent yields. This method proved to be tolerant of a broad ra...

in this study, aluminosilicate mcm-41 has been found to be an efficient catalyst for reaction betweendifferent benzaldehyde derivatives and 5,5-dimethyl-1,3-cyclohexanedione to give open chain analogue of1,8-dioxo-octahydroxanthene in excellent yields. no evidence for the formation of cyclization products wasobserved. the catalyst can be used several times after recovery.

The mesoporous molecular sieve MCM-41 was covalently grafted with 3-chloropropyl trimethoxylsilane and then was reacted with [Cr(salpr)(H2O)]Cl, (salpr = N,N'-bis(3-salicylidenaminopropyl)amine) to afford MCM-41 containing Cr(salpr) moiety, Cr(salpr)MCM-41. Powder X-ray diffraction and nitrogen adsorption-desorption analyses revealed that not only the textural characteristics of the support wer...

Upgrading of cracked PFO (Pyrolysis fuel oil) for production of fuels, such as gasoline and light gasoil, was carried out in a semi batch reactor. Two different kinds of mesoporous and microporous catalysts, MCM-41 and ZSM-5, were used. Modification methods, such as ion exchange and impregnation with Fe and Ti, were done for tuning the acidity of the catalyst. XRD, FT-IR, and XRF analyzes were ...

Our study focuses on the structural evolution of MCM-41-supported iron oxide under the reducing environment of catalyst pretreatment and ethylbenzene dehydrogenation reaction. Powder X-ray diffraction (XRD) analysis showed that the iron oxide is well-dispersed on the surface of the support with no detectable diffraction peaks from iron oxide. X-ray absorption near edge structure (XANES) study i...

A new method has been used to obtain pore size characteristics of MCM-41 catalyst supports and vanadiumsubstituted MCM-41 catalysts. The approach is based on the nonlocal density functional theory (NLDFT) model for nitrogen and argon adsorption in MCM-41, proposed recently. Samples with pore sizes varying from ca. 25 to 37 Å were prepared by hydrothermal synthesis. Two synthesis procedures empl...

A series of vanadia catalysts supported on SBA-15 (V/SBA) with a vanadia (V) content ranging from 1% to 11% were prepared by an incipient wetness method. Their catalytic behavior in the dehydrogenation of isobutane to isobutene with CO2 was examined. The catalysts were characterized by N2 adsorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and temperatur...