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Journal of Thermal Analysis and Calorimetry
Authors: Edjane F. B. Silva, Marcílio P. Ribeiro, Ana C. F. Coriolano, Ana C. R. Melo, Anne G. D. Santos, Valter J. Fernandes Jr., and Antonio S. Araujo

the need of processing large molecules present in heavy oils, the researchers from Mobil Oil Corporation developed the first family of mesostructured materials, called M41S [ 6 , 7 ], specially the MCM 41 structure, which presents an uniform hexagonal

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there is a possibility of synthesizing mesoporous materials, such as MCM-41, using FA as the source of Si. Adsorbents produced from FA could become more attractive CO 2 adsorbents than those synthesized classically, owing to, for instance, their

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Shakeel Ahmed, Faizur Rahman, Adnan M. J. Al-Amer, Eid M. Al-Mutairi, Uwais Baduruthamal, and Khurshid Alam

discovery of mesoporous materials such MCM-41 and SBA-15 provides new routes for the preparation of high performance OXDH catalysts. Liu et al. [ 4 ] studied vanadium oxide supported MgO modified SBA-15 for OXDH of n -butane and found higher C 4 -olefins

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Introduction Ordered mesoporous MCM-41 is an attractive material for many possible applications because of its high specific surface areas and uniform pore diameters [ 1 – 3 ]. In particular, this material can be used to anchor

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organized structure and specific mesopore system [ 6 ]. They can be applied to conversion of molecules of voluminous size like polymers. Recent studies show the application for mesoporous MCM-41 as active catalyst for polymer degradation [ 7 ]. The

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Abstract  

Mesoporous materials MCM-41 with the hexagonal arrangement of pores were obtained using dodecyltrimethylammonium bromide and octadecyltrimethylammonium bromide as templating surfactants. Adsorption of toluene and propan-1-ol on the as-synthesized MCM-41 silica samples was investigated using the TG-DTG, DTA and DSC techniques. The sorption mechanism of used adsorptives is discussed in terms of hydrophobicity of pore interior filled with template as well as pore dimensions.

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Abstract  

Thermal evacuation of a surfactant template from pure siliceous MCM-41 and MCM-41 containing aluminium in hydrogen flow was investigated. Micelle templated MCM-41 were prepared using hexadecyltrimethylammonium bromide (CTAB). The products of thermal surfactant degradation outside and inside pores were identified at various temperatures using 13C solid-state nuclear magnetic resonance (NMR) spectroscopy, gas chromatography coupled with mass spectrometer (GC-MS) and temperature programmed desorption coupled with mass spectrometer (TPD-MS). The GC-MS and 13C MAS NMR results obtained from this study provide an insight into the mechanism of surfactant transformation during MCM-41 synthesis on molecular level.

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Abstract  

An MCM-41-supported mercapto rhodium complex [MCM-41–SH–Rh] was conveniently synthesized from commercially available and cheap γ-mercaptopropyltriethoxysilane via immobilization on MCM-41, followed by reacting with rhodium chloride. It was found that the title complex is an efficient catalyst for the hydrosilylation reaction of olefins with triethoxysilane and can be reused several times without noticeable loss of activity.

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mechanical strength and high surface area. In this context, mesoporous MCM-41 molecular sieves with high surface area and tunable pore size came into existence [ 9 ]. The unique physical properties have made these materials highly desirable for catalytic

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Journal of Thermal Analysis and Calorimetry
Authors: Luiz K. C. de Souza, Juliana J. R. Pardauil, José R. Zamian, Geraldo N. da Rocha Filho, and Carlos E. F. da Costa

Introduction Mesoporous materials of the type MCM-41 have attracted considerable attention because of their interesting structure and potential applications in the fields of catalysis and adsorption. As a result of their high

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