Showing papers in "Microporous Materials in 1994"

TL;DR: A broad classification and survey of organic chemistry over zeolites is presented in this paper, which reflects, for the most part, a mechanistic rather than a process or applications frame of reference.

TL;DR: In this paper, the authors used IR spectroscopy at 470 K on a series of HY zeolites, including samples dealuminated either by isomorphous substitution or steaming followed by acid leaching.

TL;DR: In this paper, a comparison of SAPO-11 with other dewaxing catalysts, results for pure paraffins and wax feeds are used to gain understanding of the process chemistry.

TL;DR: In this article, the AFI and CHA structures were compared with B and Al substitution of SiO2 and Mg and Si substitution in the AlPO4 case for the conversion of methanol to hydrocarbons.

TL;DR: In this paper, the authors synthesize and characterize zeolites X and Y containing intrazeolitic cesium oxide particles and demonstrate that these materials are solid base catalysts.

TL;DR: In this article, a large CoAPO-5 crystal was synthesized by microwave heating of a fluoride-containing aluminophosphate gel and by polarization microscopy and polarization-dependent single-crystal ultraviolet-visible spectroscopy, the as-synthesized crystals showed an optical anisotropy of light absorption.

TL;DR: In this paper, an intercalation was obtained by hydrolysis of TiCl4 with HCl (TiPILCCl) and H2SO4 (TiPLS) and the influence of determinant parameters viz. the H+/Ti and Ti/clay ratios, was considered and experimental conditions leading to high specific surface areas and well defined structures of the pillared montmorillonites were determined.

TL;DR: ZSM-5 was synthesized by four methods with a gradually decreasing water content ending in a reaction mixture with absolutely dry reagents in the form of a powder in the complete absence of a solution phase.

TL;DR: In this paper, the Fickian diffusivity of n-butane through a silicalite-1 (MFI) membrane is described by a Maxwell-Stefan diffusion model in the temperature range 300-630 K, which takes into account the occupancy dependency and is consistent with an activated process having an activation energy of nearly 30 kJ mol.

TL;DR: In this paper, the high-silica molecular sieve isostructural with AlPO4-5 (AFI) is synthesized using N(16) methylsparteinium bromide as structure-directing agent and is characterized using X-ray powder diffraction (XRD), magic-angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FTIR), and the physical adsorption of N2.

TL;DR: In this paper, the authors used several proton-form mordenites (HM) and Y-zeolites (HY and LaHY) for naphthalene alkylation with isopropanol.

TL;DR: In this paper, the authors explored the synthesis parameters for the large-pore, multidimensional borosilicate SSZ-33, and found that for three given templates, there are three preferred methods of SSZ33 synthesis, exemplifying the influence of inorganic and physical factors on the synthesis process.

TL;DR: The structure of the synthetic zeolite EMC-2, in both its calcined [a=17.3741 (1) A and c=28.3646(2) A] forms, has been investigated in the space group P63/mmc using powder diffraction methods.

TL;DR: In this paper, the surface area of a pillared montmorillonite with 1.58 and 1.84 pillaring aluminum ions per unit cell and exhibiting unusual thermal stability, microporosity and Lewis/Bronsted acidity has been prepared by the reaction of the Na+ exchanged forms of the clay with Al13 oligomers formed by basic hydrolysis of aluminum trichloride.

TL;DR: In this article, the acidity of partially hydrated HY zeolite samples obtained using both 4-K broad-line and 300-K magic-angle spinning (MAS) 1H nuclear magnetic resonance (NMR) spectroscopy are discussed.

TL;DR: Oriented AlPO4-5 crystals can be embedded into a metallic grid and fixed by galvanic nickel deposition to form a membrane that is thermally stable up to 650 K.

TL;DR: In this paper, the authors compared the properties of TS-2 and VS-2 with aqueous hydrogen peroxide and showed that the principal path is probably homolytic in the case of the latter.

TL;DR: In this paper, the synthesis and characterization of hexadeca- or perfluorophthalocyanine complexes of iron(II) (FeF 16 Pc) in synthetic faujasite-type zeolites is reported.

TL;DR: Titanium-containing pure-silica ZSM-5 (TS-1), pure-silica X-ray powder diffraction (XRD), elemental analysis, physical adsorption of nitrogen, Fourier transform infrared (FTIR), FT-Raman, and ultraviolet-visible (UV-VIS) spectroscopies were used in this paper to evaluate the physicochemical and catalytic properties of titanium-containing zeolites.

TL;DR: In this article, the authors characterized wet and dry precursor gels by diffuse reflectance spectroscopy (DRS) and showed that triethylamine has in the first place a pH-regulating effect.

TL;DR: In this article, the acid properties of isomorphously substituted MFI-type zeolites prepared and pretreated in the same way were studied to obtain an exact gradient of the intrinsic acidity caused by the incorporation of Ga, Fe, In and B instead of Al into the framework.

TL;DR: In this paper, the structure determination from X-ray diffraction (XRD) data, obtained with a single crystal, shows that four different templates are located in four sites of the cages and cavities: F − in the D4R, N(CH 3 ) + 4 in the sodalite cage, diethanolamine and water in the eight-ring and near the six-ring of the large α cage, respectively.

TL;DR: In this article, the relationship between in-going ion loading and selectivity was fitted to third-order polynomial equations, and the polynomials coefficients and the error of the fits are presented.

TL;DR: The tetragonal variant of AlPO4-16 isostructural of the clathrasil octadecasil was obtained by using quinuclidine as a template in the presence of fluoride anions as mentioned in this paper.

TL;DR: In this paper, a series of Ti-Beta zeolites with different titanium contents were investigated by X-ray photoelectron spectroscopy (XPS) and compared with the spectra obtained for two naturally occurring titano-silicates.

TL;DR: In this article, the micropore range can be divided into five regions, corresponding to pores filled with one to five layers of nitrogen molecules, and corresponding relative pressure intervals in which the pores in a certain pore size region are filled are assigned by using several PILC samples with different but known pore widths.

TL;DR: In this paper, a method of PILC preparation with concentrated slurries is reported and the PILCs produced are compared with those obtained from diluted clay suspensions, and the structure collapsed with a specific surface area from 8 to 27 m 2 /g depending on the preparation method.

TL;DR: In this paper, the organosilicon compound N-trimethoxysilylpropyltri-N- butylammonium was used as a structure-directing agent for the synthesis of new microporous materials.

TL;DR: In this paper, a synthesis of crystalline ferrisilicate having zeolite BEA topology (Fe-Beta) and containing significant quantities of iron in the framework was reported.

TL;DR: In this article, the properties of self-assembled films of insoluble surfactants and surfactant composites and their applications to electrochemical catalysis are reviewed and discussed.