Results 231 to 240 of about 13,427 (273)

Rearrangement of allyl phenyl ether over Al-MCM-41

Journal of Catalysis, 2005
Claisen rearrangement of allyl phenyl ether to o-allylphenol and a dihydrobenzofuran derivative was investigated over MCM-41 with different Si/Al ratios. Higher aluminum content, higher reaction temperatures, and longer run duration favor the formation of the ring compound 2,3-dihydro-2-methyl benzofuran.
N MATHEW, S KHAIRE, S MAYADEVI, R JHA, S SIVASANKER   +4 more
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Al-MCM-41 catalysed alkylation of phenol with methanol

Journal of Molecular Catalysis A: Chemical, 2003
Abstract Mesoporous Al-MCM-41 molecular sieve materials with three different SiO2/Al2O3 ratios were used as catalysts for phenol methylation with methanol as the alkylating agent. Reaction conditions such as temperature, feed flow rate, the reactant mole ratio and the catalyst SiO2/Al2O3 ratio have significant influence on the distribution of ...
Krishna G. Bhattacharyya, Anup K. Talukdar, Parashmani Das, S. Sivasanker   +3 more
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Remarkable acceleration of cyanosilylation by the mesoporous Al-MCM-41 catalyst

Chemical Communications, 2008
The presence of the heterogeneous mesoporous Al-MCM-41 catalyst remarkably accelerated the cyanosilylation of various aldehydes and ketones with trialkylsilyl cyanide, giving the corresponding cyanohydrin silyl ethers in quantitative yields under mild reaction conditions.
Katsuyuki, Iwanami, Jun-Chul, Choi, Baowang, Lu, Toshiyasu, Sakakura, Hiroyuki, Yasuda   +4 more
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Characteristics of Al-MCM-41 supported Pt catalysts: effect of Al distribution in Al-MCM-41 on its catalytic activity in naphthalene hydrogenation

Catalysis Today, 2002
Abstract Naphthalene hydrogenation was carried out in a high-pressure batch reactor over platinum catalysts supported on Al-MCM-41 where aluminum was incorporated through two different methods: a direct sol–gel method (Pre) and post-synthetic grafting method (Post).
Kwang-Cheon Park, Dae-Jae Yim, Son-Ki Ihm   +2 more
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Selective catalytic reduction of NO over Cu-Al-MCM-41

Journal of Catalysis, 2004
Al-MCM-41 and Cu-Al-MCM-41 were prepared by a modified hydrothermal method. The characterization using XRD, NMR, and N2 adsorption isotherms revealed that the structure of Al-MCM-41 remained unchanged after the complete exchange of protons for copper ions.
Y WAN, J MA, Z WANG, W ZHOU, S KALIAGUINE   +4 more
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Synthesis and characterization of bimetallic Ga,Al-MCM-41 and Fe,Al-MCM-41

2002
The structural and acidic properties of bimetallic Fe,Al-MCM-41 and Ga,Al-MCM-41 were compared with the Al-MCM-41. The competitive presence of Al and Fe/Ga in the MCM-41 walls and the formation of extra-framework Al and Fe/Ga species induces changes in the nature of the acid sites and therefore of their catalytic properties.
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Al-MCM-41: its acidity and activity in cyclohexene conversion

Physical Chemistry Chemical Physics, 2001
Investigation of cyclohexene conversion over Al-MCM-41 has shown that the concentrations of Bronsted and Lewis acid sites increase with the Al content of the materials. The conversion follows mainly two mechanisms: cyclohexene skeletal isomerisation (CSI) and hydrogen transfer (HT).
Michal Rozwadowski, Jerzy Datka, Maria Lezanska, Jerzy Wloch, Krzysztof Erdmann, Jan Kornatowski   +5 more
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Synthesis of Al-MCM-41 and FCC diesel hydrorefining study

Journal of Porous Materials, 2011
Mesostructured aluminosilicates (MCM-41) with ordered 2-dimensional hexagonal structure were successfully synthesized via the alkali-treatment step and nanocrystal aluminosilicates assembly in the basic and hydrothermal synthesis conditions by sol–gel approach.
Zhanquan Zhang, Jun Xiao, Lei Dai, Yingying Wang, DongQing Wang, Xinmei Liu, Zifeng Yan   +6 more
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Coordination state of Cu+ ions in Cu-[Al]MCM-41

Applied Catalysis B: Environmental, 2011
Abstract A Cu-[Al]MCM-41 sample was studied by FTIR spectroscopy of probe molecules (CO and NO) and methanol conversion test reaction. It was found that the parent MCM-41 material was characterized by the practical absence of strongly acidic hydroxyl groups (typical of zeolites), but possessed some hydroxyls with a moderate acidity.
K. Chakarova, G. Petrova, M. Dimitrov, L. Dimitrov, G. Vayssilov, T. Tsoncheva, K. Hadjiivanov   +6 more
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Highly hydrothermally stable Al-MCM-41 with accessible void defects

Journal of Porous Materials, 2012
Mesoporous aluminosilicates (Al-MCM-41) with high hydrothermal stability were synthesized via self-assembly of nanoseed precursors, obtained from alkali-treatment of ZSM-5. Characterized by N2 sorption, Transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and Mercury intrusion, as-prepared Al-MCM-41 possessed a ...
Zhanquan Zhang, Zifeng Yan
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