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Preparation of Al-MCM-41 materials and PS/Al-MCM-41 composite using supercritical carbon dioxide
Materials Science and Engineering: B, 2005Supercritical carbon dioxide (SC CO2) was used as carriers/solvent for “dry” alumination of mesoporous silica to prepare Al-MCM-41. The effect of aluminum on the structure and crystallinity of the materials was studied. Further, styrene monomer was impregnated into MCM-41 and Al-MCM-41 with the assistance of SC CO2, and then was polymerized in the ...
Qun Xu +5 more
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Metastability of MCM-41 and Al-MCM-41
The Journal of Physical Chemistry A, 2008The apparent stability of MCM-41 and Al-MCM-41 in water was appraised in a series of solubility experiments. MCM-41 is a siliceous, mesoporous material of hexagonal symmetry and exceptionally high surface area first synthesized in 1992. The dissolution experiments were carried out at several solid/water ratios: 1/200, 1/100, and 1/75. Results indicated
Colin P, Guthrie, Eric J, Reardon
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Catalytic Pyrolysis of Waste Achyranthes Root Over Al-MCM-41
Journal of Nanoscience and Nanotechnology, 2021This study examined the thermal and catalytic pyrolysis of waste Achyranthes Root (AR) using pyrolyzer-gas chromatography/mass spectrometry (Py-GC/MS). The non-catalytic pyrolysis of waste AR produced various kinds of oxygenates, such as acetic acid, hydroxy propanone, furfural, phenol, cresol, guaiacols, syringols, and so on.
Seul-Bee, Lee +3 more
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Al-MCM-41 as methanol dehydration catalyst
Applied Catalysis A: General, 2010Abstract Al-MCM-41, [SiO2]/[Al2O3] = 30, mesoporous catalysts were synthesized using tetraethylorthosilicate (TEOS) as a source of silica and hexadecyltrimethylammonium bromide (CTAB) as a structure-directing agent (SDA) in the presence of tetrapropylammonium hydroxide (TPAOH) as a co-surfactant additive.
Sajo P. Naik +4 more
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Several factors affecting Al-MCM-41 synthesis
Microporous and Mesoporous Materials, 2001Abstract Several mesoporous aluminosilicate molecular sieves with the MCM-41 structure (Si/Al=24) have been synthesized using different aluminum and silica sources and varying several synthesis parameters during the preparation process such as the use of an anti-foaming agent, prior aging of the gel mixture or pH adjustment of the gel mixture under ...
Y. Cesteros, G.L. Haller
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ESTUDO DO COMPORTAMENTO TÉRMICO E CINÉTICO DO ÓLEO DE MAMONA SUPORTADO EM AL-MCM-41 E MONI/AL-MCM-41
2023A busca por fontes energéticas mais limpas, visando a substituição dos combustíveis fósseis, faz da biomassa uma alternativa bastante promissora. Diante disso, o estudo térmico e cinético de uma determinada matéria-prima é um processo bastante importante para a visualização de sua viabilidade na geração de biocombustíveis, pois fornece informações ...
Victória Victor Soares +6 more
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Mesoporous material Al-MCM-41 from natural halloysite
Physics and Chemistry of Minerals, 2014Aluminum-containing hexagonally ordered mesoporous silica (Al-MCM-41) with specific surface area of 509.4 m2/g was first synthesized using natural halloysite as source material by hydrothermal treatment, without addition of silica or aluminum regents. The samples were characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption ...
Yaling Xie +3 more
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Acidity and active sites of Al-MCM-41
Applied Catalysis A: General, 1999Abstract The influence of the aluminum contents of MCM-41 (Si/Al ratio varied between 2.7 and 69) on the coordination of Al, on the acidity, and on the catalytic properties is studied by 27Al MAS NMR, temperature programmed desorption of ammonia, and the conversion of acetone. Based on TPDA results, an assignment of the peaks of desorption of ammonia
H Kosslick +4 more
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Investigation of Coke Deposits on Al-MCM-41
Chemistry of Materials, 2001Carbonaceous compounds deposited on aluminosilicate mesoporous molecular sieves of the MCM-41 type during conversion of cyclohexene at various temperatures were investigated using TGA; DRIFT, UV−vis, and 13C solid state NMR spectroscopies; and a sorption technique. The chemical composition of the deposits is not significantly affected by the Al content
M. Rozwadowski +5 more
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Synthesis of Dicyclopentadiene Oligomer Over Nanoporous Al-MCM-41 Catalysts
Journal of Nanoscience and Nanotechnology, 2016One step reaction composed of DCPD oligomerization and DCPD oligomer isomerization was investigated over nanoporous Al-MCM-41 catalysts. The effects of aluminum grafting over MCM-41 on the catalyst characteristics were studied with respect to the synthesis of TCPD isomer. Physical and chemical properties of the catalysts were analyzed by N2 adsorption,
Eunseo, Park +6 more
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