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Abstract  

β-MCM41 composite molecular sieves were hydrothermally synthesized using NaOH treated β zeolite as precursors, and Pt/β-MCM41 bifunctional catalysts were prepared by impregnation. Hβ, desilicated Hβ by NaOH treatment (Dβ), and the physical mixture of Hβ and MCM41 (β+MCM41) were also used as control supports for bifunctional catalysts. All the catalysts were characterized by ICP, XRD, BET, nitrogen adsorption–desorption isotherm and NH3-TPD, and evaluated in the hydroisomerization of n-heptane using an atmospheric fixed bed flow reactor. Dβ, β+MCM41, or β-MCM41 supported Pt catalysts showed higher selectivity to isoheptanes than the counterpart Pt/Hβ did due to the presence of mesopores in addition to the zeolite micropores. Moreover, Pt/β-MCM41 was demonstrated to be a much more selective catalyst among them because the connection between mesopores and micropores accelerated the diffusion of larger molecules of isoheptanes. Under optimal conditions, Pt/β-MCM41 provided a very high selectivity to isomerization of 96.5%, coupled with a considerable high conversion of n-heptane of 56.0%.

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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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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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], herein, we report the effect of immobilized tridentate N -salicylidene- l -histidine Schiff base vanadium complex within the nanoreactors of Al-MCM-41 as catalysts for the epoxidation of geraniol, cinnamyl alcohol and trans -2-hexene-1-ol

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Journal of Thermal Analysis and Calorimetry
Authors: Marcela N. Barbosa, Antonio S. Araujo, Luzia P. F. C. Galvão, Edjane F. B. Silva, Anne G. D. Santos, Geraldo E. Luz Jr., and Valter J. Fernandes Jr.

organic molecules, metals or polymers. The high surface area, well defined structure and good thermal stability are characteristics of mesoporous materials such as MCM-41 and SBA-15, for application in various processes, for example, adsorption process. It

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Journal of Thermal Analysis and Calorimetry
Authors: Késia K. V. Castro, Ana A. D. Paulino, Edjane F. B. Silva, Thiago Chellappa, Maria B. D. L. Lago, Valter J. Fernandes Jr., and Antonio S. Araujo

structure of mesoporous materials can be visualized in other major works [ 5 , 6 ]. The presence of the hydroxyl groups associated with a tetracoordinated metal, such as, aluminum, within the framework of MCM-41 favors the Bronsted acidity, improving the

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