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Jeffrey S. Beck

Bio: Jeffrey S. Beck is an academic researcher from Mobil. The author has contributed to research in topics: Molecular sieve & Mesoporous material. The author has an hindex of 19, co-authored 45 publications receiving 11983 citations.

Papers
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Patent
28 May 1993
TL;DR: In this paper, a shape selective hydrocarbon conversion that involves contacting a hydrocarbon feedsteam, including toluene, under conversion conditions with a catalytic molecular sieve which has been modified by being ex situ selectivated with a silicon compound is described.
Abstract: A process for shape selective hydrocarbon conversion that involves contacting a hydrocarbon feedsteam, including toluene, under conversion conditions with a catalytic molecular sieve which has been modified by being ex situ selectivated with a silicon compound. The ex situ selectivation involves exposing the molecular sieve to at least two silicon impregnation sequences, each sequence comprising an impregnation with a silicon compound followed by calcination. The modified catalyst used in the process may also be steamed. Optionally, the modified catalyst may be trim-selectivated.

71 citations

Patent
28 May 1993
TL;DR: In this paper, an ex situ selectivated catalytic molecular sieve for enhanced shape selective hydrocarbon conversions is described, in which a catalytic mixtures is modified by being exposed to at least two selectivation sequences, each sequence including an impregnation of the mixtures with a selectivating agent and a subsequent calcination of the impregnated mixtures.
Abstract: An ex situ selectivated catalytic molecular sieve for enhanced shape selective hydrocarbon conversions in which a catalytic molecular sieve is modified by being exposed to at least two selectivation sequences, each sequence including an impregnation of the molecular sieve with a selectivating agent and a subsequent calcination of the impregnated molecular sieve. The ex situ selectivation method is also described, including the use of low volatility organic carriers for the selectivating agent. Also, a method for moderate steaming of the ex situ selectivated molecular sieve. Also a method for in situ trim-selectivating the ex situ selectivated catalytic molecular sieve. Also described is the process for shape selective hydrocarbon conversion comprising contacting a hydrocarbon feedstream under conversion conditions with the modified catalytic molecular sieve.

62 citations

Patent
22 Dec 1992
TL;DR: In this article, a method for synthesizing a new synthetic composition of ultra-large pore crystalline material which can be used as a sorbent or catalyst component for conversion of organic and inorganic compounds is provided.
Abstract: There is provided a method for synthesizing a new synthetic composition of ultra-large pore crystalline material which can be used as a sorbent or catalyst component for conversion of organic and inorganic compounds. The crystalline material product of this method exhibits unusually large sorption capacity demonstrated by its benzene adsorption capacity of greater than about 15 grams benzene/100 grams at 50 torr and 25° C. This material may have a hexagonal electron diffraction pattern that can be indexed with a d100 value greater than about 18 Angstrom Units and a hexagonal arrangement of uniformly sized pores with a maximum perpendicular cross section of at least about 13 Angstrom units. The reaction mixture for preparing this material is prepared by forming a solution containing a source of an oxide, followed by adding a gelling reagent to this solution to form a gel.

59 citations

Patent
05 Jun 1995
TL;DR: In this article, an ex situ selectivated catalytic molecular sieve for shape selective aromatic alkylation is presented, in which a reduced activity is modified by being exposed to at least two selectivation sequences and then reduced in activity.
Abstract: The present invention is a method of producing an ex situ selectivated catalytic molecular sieve for shape selective aromatic alkylation in which a catalytic molecular sieve having a reduced activity is modified by being exposed to at least two selectivation sequences, each sequence includes contacting the molecular sieve with a selectivating agent and subsequently calcining the contacted molecular sieve. The present invention is also a method of producing an ex situ selectivated catalytic molecular sieve for shape selective aromatic alkylation in which a catalytic molecular sieve is modified by being exposed to at least two selectivation sequences and then reduced in activity. The ex situ selectivated catalytic molecular sieves may optionally be further modified by in situ trim selectivation. The present invention is also a process for shape selective aromatic alkylation utilizing the modified molecular sieves.

50 citations


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Journal ArticleDOI
23 Jan 1998-Science
TL;DR: Use of amphiphilic triblock copolymers to direct the organization of polymerizing silica species has resulted in the preparation of well-ordered hexagonal mesoporous silica structures (SBA-15) with uniform pore sizes up to approximately 300 angstroms.
Abstract: Use of amphiphilic triblock copolymers to direct the organization of polymerizing silica species has resulted in the preparation of well-ordered hexagonal mesoporous silica structures (SBA-15) with uniform pore sizes up to approximately 300 angstroms. The SBA-15 materials are synthesized in acidic media to produce highly ordered, two-dimensional hexagonal (space group p6mm) silica-block copolymer mesophases. Calcination at 500°C gives porous structures with unusually large interlattice d spacings of 74.5 to 320 angstroms between the (100) planes, pore sizes from 46 to 300 angstroms, pore volume fractions up to 0.85, and silica wall thicknesses of 31 to 64 angstroms. SBA-15 can be readily prepared over a wide range of uniform pore sizes and pore wall thicknesses at low temperature (35° to 80°C), using a variety of poly(alkylene oxide) triblock copolymers and by the addition of cosolvent organic molecules. The block copolymer species can be recovered for reuse by solvent extraction with ethanol or removed by heating at 140°C for 3 hours, in both cases, yielding a product that is thermally stable in boiling water.

10,807 citations

Journal ArticleDOI
TL;DR: In this paper, a family of highly ordered mesoporous (20−300 A) structures have been synthesized by the use of commercially available nonionic alkyl poly(ethylene oxide) (PEO) oligomeric surfactants and poly(alkylene oxide) block copolymers in acid media.
Abstract: A family of highly ordered mesoporous (20−300 A) silica structures have been synthesized by the use of commercially available nonionic alkyl poly(ethylene oxide) (PEO) oligomeric surfactants and poly(alkylene oxide) block copolymers in acid media. Periodic arrangements of mescoscopically ordered pores with cubic Im3m, cubic Pm3m (or others), 3-d hexagonal (P63/mmc), 2-d hexagonal (p6mm), and lamellar (Lα) symmetries have been prepared. Under acidic conditions at room temperature, the nonionic oligomeric surfactants frequently form cubic or 3-d hexagonal mesoporous silica structures, while the nonionic triblock copolymers tend to form hexagonal (p6mm) mesoporous silica structures. A cubic mesoporous silica structure (SBA-11) with Pm3m diffraction symmetry has been synthesized in the presence of C16H33(OCH2CH2)10OH (C16EO10) surfactant species, while a 3-d hexagonal (P63/mmc) mesoporous silica structure (SBA-12) results when C18EO10 is used. Surfactants with short EO segments tend to form lamellar mesost...

6,274 citations

Journal ArticleDOI
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.
Abstract: It is possible to say that zeolites are the most widely used catalysts in industry They are crystalline microporous materials which have become extremely successful as catalysts for oil refining, petrochemistry, and organic synthesis in the production of fine and speciality chemicals, particularly when dealing with molecules having kinetic diameters below 10 A The reason for their success in catalysis is related to the following specific features of these materials:1 (1) They have very high surface area and adsorption capacity (2) The adsorption properties of the zeolites can be controlled, and they can be varied from hydrophobic to hydrophilic type materials (3) Active sites, such as acid sites for instance, can be generated in the framework and their strength and concentration can be tailored for a particular application (4) The sizes of their channels and cavities are in the range typical for many molecules of interest (5-12 A), and the strong electric fields2 existing in those micropores together with an electronic confinement of the guest molecules3 are responsible for a preactivation of the reactants (5) Their intricate channel structure allows the zeolites to present different types of shape selectivity, ie, product, reactant, and transition state, which can be used to direct a given catalytic reaction toward the desired product avoiding undesired side reactions (6) All of these properties of zeolites, which are of paramount importance in catalysis and make them attractive choices for the types of processes listed above, are ultimately dependent on the thermal and hydrothermal stability of these materials In the case of zeolites, they can be activated to produce very stable materials not just resistant to heat and steam but also to chemical attacks Avelino Corma Canos was born in Moncofar, Spain, in 1951 He studied chemistry at the Universidad de Valencia (1967−1973) and received his PhD at the Universidad Complutense de Madrid in 1976 He became director of the Instituto de Tecnologia Quimica (UPV-CSIC) at the Universidad Politecnica de Valencia in 1990 His current research field is zeolites as catalysts, covering aspects of synthesis, characterization and reactivity in acid−base and redox catalysis A Corma has written about 250 articles on these subjects in international journals, three books, and a number of reviews and book chapters He is a member of the Editorial Board of Zeolites, Catalysis Review Science and Engineering, Catalysis Letters, Applied Catalysis, Journal of Molecular Catalysis, Research Trends, CaTTech, and Journal of the Chemical Society, Chemical Communications A Corma is coauthor of 20 patents, five of them being for commercial applications He has been awarded with the Dupont Award on new materials (1995), and the Spanish National Award “Leonardo Torres Quevedo” on Technology Research (1996) 2373 Chem Rev 1997, 97, 2373−2419

5,290 citations

Journal ArticleDOI
TL;DR: The state-of-the-art on hybrid porous solids, their advantages, their new routes of synthesis, the structural concepts useful for their 'design', aiming at reaching very large pores are presented.
Abstract: This critical review will be of interest to the experts in porous solids (including catalysis), but also solid state chemists and physicists. It presents the state-of-the-art on hybrid porous solids, their advantages, their new routes of synthesis, the structural concepts useful for their ‘design’, aiming at reaching very large pores. Their dynamic properties and the possibility of predicting their structure are described. The large tunability of the pore size leads to unprecedented properties and applications. They concern adsorption of species, storage and delivery and the physical properties of the dense phases. (323 references)

5,187 citations

Journal ArticleDOI
23 Dec 1994-Science
TL;DR: A relatively new method for preparing nanomaterials, membrane-based synthesis, is reviewed, which entails synthesis of the desired material within the pores of a nanoporous membrane.
Abstract: Materials with nanoscopic dimensions not only have potential technological applications in areas such as device technology and drug delivery but also are of fundamental interest in that the properties of a material can change in this regime of transition between the bulk and molecular scales. In this article, a relatively new method for preparing nanomaterials, membrane-based synthesis, is reviewed. This method entails synthesis of the desired material within the pores of a nanoporous membrane. Because the membranes used contain cylindrical pores of uniform diameter, monodisperse nanocylinders of the desired material, whose dimensions can be carefully controlled, are obtained. This "template" method has been used to prepare polymers, metals, semiconductors, and other materials on a nanoscopic scale.

3,887 citations