Journal ArticleDOI
Transition metal substituted derivatives of cubic MCM-48 mesoporous molecular sieves
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In this article, the mesoporous Ti-, Cr- and V-substituted derivatives of the cubic silica molecular sieve MCM-48 have been synthesized at 373 K by an electrostatic assembly pathway using cetyltrimethylammonium cation as the templating agent.Abstract:
Mesoporous Ti-, Cr- and V-substituted derivatives of the cubic silica molecular sieve MCM-48 have been hydrothermally synthesized at 373 K by an electrostatic assembly pathway using cetyltrimethylammonium cation as the templating agent. The transition metal substituted products all exhibit improved crystallinity and a narrower pore size distribution relative to the pristine molecular sieve. Transition metal substitution caused an enlargement of the cubic unit cell as well as an increase in the degree of crosslinking in the mesopore walls. The coordination of V-sites in the meso-structure is exclusively tetrahedral, as judged by NMR spectroscopy. These sites as well as those of Ti and Cr sites are active and selective for the peroxide oxidation of styrene and methyl methacrylate to benzaldehyde and methyl pyruvate, respectively.read more
Citations
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From Microporous to Mesoporous Molecular-Sieve Materials and Their Use in Catalysis
TL;DR: Corma et al. as mentioned in this paper used the Dupont Award on new materials (1995), and the Spanish National Award “Leonardo Torres Quevedo” on Technology Research (1996) on technology research (1996), to recognize the performance of zeolites as catalysts for oil refining and petrochemistry.
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Perspectives in catalytic applications of mesostructured materials
TL;DR: In this paper, a review paper deals with proven and potential applications of mesoporous molecular sieves in catalysis, and is divided into two parts, respectively, dedicated to the design of solid catalysts and catalyst supports and to some relevant examples of catalytic processes.
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The structure of active centers and the ethylene polymerization mechanism on the Cr/SiO2 catalyst: a frontier for the characterization methods.
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Direct Synthesis of Hybrid Organic−Inorganic Nanoporous Silica by a Neutral Amine Assembly Route: Structure−Function Control by Stoichiometric Incorporation of Organosiloxane Molecules
TL;DR: In this paper, two distinct approaches for the formation of hybrid inorganic−organic compounds, denoted as the template substitution and direct addition pathways, were considered for the functionalization of mesostructures with moieties whose size is comparable to that of the structure-directing amine surfactant.
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Modification of mesoporous silicas by incorporation of heteroelements in the framework
TL;DR: In this article, the authors present a piece of the work that has been achieved over the last years in the field of synthesis and characterization of mesoporous silicas modified by different metals.
References
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Journal ArticleDOI
A new family of mesoporous molecular sieves prepared with liquid crystal templates
Jeffrey S. Beck,James C. Vartuli,Wieslaw J. Roth,M. E. Leonowicz,Charles T. Kresge,Kirk D. Schmitt,Cynthia Ting-Wah Chu,David H. Olson,E. W. Sheppard,S. B. McCullen,J. B. Higgins,J.L. Schlenker +11 more
TL;DR: In this paper, the synthesis, characterization, and proposed mechanism of formation of a new family of silicatelaluminosilicate mesoporous molecular sieves designated as M41S is described.
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Generalized synthesis of periodic surfactant/inorganic composite materials
Qisheng Huo,David I. Margolese,Ulrike Ciesla,Pingyun Feng,Thurman E. Gier,Peter Sieger,R. Leon,Pierre Petroff,Ferdi Schüth,Ferdi Schüth,Galen D. Stucky +10 more
TL;DR: In this article, a generalized approach to the synthesis of periodic mesophases of metal oxides and cationic or anionic surfactants under a range of pH conditions is presented.
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A neutral templating route to mesoporous molecular sieves.
TL;DR: A neutral templating route for preparing mesoporous molecular sieves is demonstrated based on hydrogen-bonding interactions and self-assembly between neutral primary amine micelles (S�) and neutral inorganic precursors (l�).
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Titanium-containing mesoporous molecular sieves for catalytic oxidation of aromatic compounds
TL;DR: The use of the templating approach to synthesize mesoporous silica-based molecular sieves partly substituted with titanium—large-pore analogues of titanium silicalite find that these materials show selective catalytic activity towards the oxidation of 2,6-ditert-butyl phenol to the corresponding quinone and the conversion of benzene to phenol.
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Studies on mesoporous materials: I. Synthesis and characterization of MCM-41
TL;DR: The mesoporous molecular sieves MCM-41 were synthesized and characterized by X-ray powder diffraction, nitrogen adsorption/desorption, cyclohexane and water adaption, transmission electron micrographs (TEM), thermogravimetric analysis (TGA), ammonia temperature-programmed desorption (TPD), FTIR, FT-Raman, 29Si, 27Al and 13C magic angle spinning (MAS) NMR spectroscopy.