Template-free synthesis of highly selective amorphous aluminosilicate catalyst for toluene alkylation

Dimensionally-Controlled Hydrothermal Tm3+-doped Oxidic Nanocrystals and Their Photoluminescence Properties

MRS Proceedings ◽

10.1557/proc-1247-c04-15 ◽

2010 ◽

Vol 1247 ◽

Author(s):

Rocío Calderón-Villajos ◽

Carlos Zaldo ◽

Concepción Cascales

Keyword(s):

Single Crystals ◽

Fluorescence Lifetimes ◽

Photoluminescence Properties ◽

Reaction Conditions ◽

Hydrothermal Processes ◽

Bulk Single Crystals ◽

Template Free ◽

Reaction Media

AbstractControlled reaction conditions in simple, template-free hydrothermal processes yield Tm-Lu2O3 and Tm-GdVO4 nanocrystals with well-defined specific morphologies and sizes. In both oxide families, nanocrystals prepared at pH 7 reaction media exhibit photoluminescence in ∼1.95 μm similar to bulk single crystals. For the lowest Tm3+ concentration (0.2 % mol) in GdVO4 measured 3H4 and 3F4 fluorescence lifetimes τ are very near to τrad.

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Electrochemical Deposition of Polypyrrole Nanostructures for Energy Applications: A Review

Current Nanoscience ◽

10.2174/1573413715666190717113600 ◽

2020 ◽

Vol 16 (4) ◽

pp. 462-477 ◽

Cited By ~ 2

Author(s):

Patrizia Bocchetta ◽

Domenico Frattini ◽

Miriana Tagliente ◽

Filippo Selleri

Keyword(s):

Lithium Batteries ◽

High Performance ◽

Relevant Literature ◽

Chemical Parameters ◽

Energy Devices ◽

Energy Applications ◽

Physico Chemical ◽

Potential Applications ◽

Template Free ◽

Cathodic Polymerization

By collecting and analyzing relevant literature results, we demonstrate that the nanostructuring of polypyrrole (PPy) electrodes is a crucial strategy to achieve high performance and stability in energy devices such as fuel cells, lithium batteries and supercapacitors. In this critic and comprehensive review, we focus the attention on the electrochemical methods for deposition of PPy, nanostructures and potential applications, by analyzing the effect of different physico-chemical parameters, electro-oxidative conditions including template-based or template-free depositions and cathodic polymerization. Diverse interfaces and morphologies of polymer nanodeposits are also discussed.

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The Effect of Acidity of Al and Fe Silicates with MFI Structure on Benzene and Toluene Alkylation with Isopropyl Alcohol

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19961115 ◽

1996 ◽

Vol 61 (8) ◽

pp. 1115-1130 ◽

Cited By ~ 2

Author(s):

Jiří Čejka ◽

Naděžda Žilková ◽

Blanka Wichterlová

Keyword(s):

Kinetic Study ◽

Molecular Sieves ◽

Isopropyl Alcohol ◽

Acid Sites ◽

Transport Rate ◽

Reaction Products ◽

Oh Groups ◽

Benzene Alkylation ◽

Toluene Alkylation ◽

Low Strength

Kinetic study of toluene and benzene alkylation with isopropyl alcohol on alumo- and ferrisilicates of MFI structure has shown that the alkylation activity does not follow the acidity (both the number and strength of bridging OH groups) of these molecular sieves. The rate of the overall reaction is controlled by the desorption/transport rate of bulky, strongly adsorbed cymenes and cumene. A higher concentration of n-propyltoluenes compared to n-propylbenzene, both undesired reaction products, formed via a bimolecular isomerization of isopropyl aromate with benzene or toluene, was due to the higher reactivity of isopropyltoluene with toluene in comparison with that of cumene with benzene. It is concluded that ferrisilicates of MFI structure possessing low strength acid sites appear to be promising catalysts for achieving both a high isopropyl- and para-selectivity in toluene alkylation to p-cymene.

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