Molecular-sieve zeolites, Nafion membranes, low-density polyethylene films, and mixed surfactant vesicles have been used as microreactors to carry out organic photochemical reactions. The photo-cycloadditions of diaryl compounds with long flexible chains included in NaY zeolite or low-density polyethylene films yield intramolecular photocyclomers to the exclusion of intermolecular products. The...

Ultrathin MFI-zeolite nanosheets can be packed on porous supports to create molecular sieve membranes. The nanosheets on porous support reduce morphological damage seen in regular MFIzeolite crystals [1]. MFI-zeolite belongs to pentasil family of zeolites where the periodic building unit (PerBU) is composed of 12 interconnected SiO4 tetrahedral (T12) units of 41m2 (D2d) symmetry [2]. Rotation o...

in order to gain a better understanding of the chemistry of methanl-to-hydro-carbon conversion, it is necessary to determine the nature of the primary reaction products. experiments carried out in this work on h-zsm-11, using a continuous flow reactor linked to an on-line gas chromatograph demonstrated that ethylene and methane are the primary reaction products. the results obtained using solid...

Zeolites are crystalline inorganic porous materials formed by TO4 tetrahedra (T=Si, Al, P, etc.) with ordered microporous structures. As a result of their tunable acidities and framework structures, zeolites have been used widely in catalysis and molecular adsorption/separation as well as several other emerging applications. However, the pore size of a zeolite is usually smaller than 2 nm, whic...

Identification of the catalyst characteristics correlating with key performance parameters including selectivity and stability is to rational design. Herein we focused on identification property-performance relationships in methanol-to-olefin (MTO) process by studying detail catalytic behaviour MFI, MEL their respective intergrowth zeolites. The detailed material characterization reveals that b...

In order to gain a better understanding of the chemistry of methanl-to-hydro-carbon conversion, it is necessary to determine the nature of the primary reaction products. Experiments carried out in this work on H-ZSM-11, using a continuous flow reactor linked to an on-line gas chromatograph demonstrated that ethylene and methane are the primary reaction products. The results obtained using s...

Exploring advanced catalysts and reaction systems operated at mild conditions is crucial for conducting the direct methane oxidation toward oxygenate products. Many efforts have been put into research on pentasil−type (MFI) zeolites based mononuclear and/or binuclear iron sites, using H2O2 as oxidant. In this work, we present a modified liquid ion−exchange method to better control Fe loading in...

Stacking faults are two-dimensional planar defects frequently arising in zeolites, modifying their properties and potentially affecting performance catalysis separation applications. In classical zeolite intergrowths, a topologically unique layer may often pile up after some spatial transformation (lateral translation, rotation, and/or reflection) that occur different amounts or directions with...

The structure of phenylcyclopropane radical cation (1•+, R ) H) is derived from CIDNP effects observed during the electron transfer reaction of 1 with chloranil. This species is an example of an elusive structure type. The secondary cyclopropane protons show significantly divergent hyperfine coupling constants due to an unprecedented stereoelectronic effect. Incorporation into a redox-active pe...

Natural zeolites occur in over 40 countries and are mined in 11 of these at a rate of around 250 thousand tonnes per year. Discovery of the characteristic ion-exchange, dehydration and selective-adsorption properties of these zeolites, which are related to their unique honeycomb structure, stimulated the development of severa1 processes for the manufacture of synthetic zeolites. These synthetic...