Cesium concentration effect on Pt/Cs beta zeolite/γ-alumina catalysts for n-heptane conversion

Molecular sieves with beta zeolite topology are promising catalysts for various reactions as they exhibits extraordinary Lewis acidity. However, their industrial application and related research in academica is hindered because their synthesis is time consuming and typically involves toxic chemicals as hydrofluoric acid. Therefore, tetraethylammonium fluorid was tested as a non-toxic fluotide source for the synthesis of beta zeolites. In combination with the previously reported nano-seeded growth method, a fast synthesis of beta zeolites only involving non-toxic chemicals was possible. Synthesized zeolites show comparable selectivity in the Bayer-Villinger oxidation as conventional zeolites synthesized with hydrofluoric acid.<br>

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Performance of Ag-HZSM-5 Zeolite Catalysts in n-heptane Conversion

Revista de Chimie ◽

10.37358/rc.17.1.5401 ◽

2017 ◽

Vol 68 (1) ◽

pp. 116-120

Author(s):

Iuliean Vasile Asaftei ◽

Neculai Catalin Lungu ◽

Lucian Mihail Birsa ◽

Ioan Gabriel Sandu ◽

Laura Gabriela Sarbu ◽

...

Keyword(s):

Aromatic Hydrocarbons ◽

Metal Content ◽

Pulse Method ◽

Acid Strength ◽

Strength Distribution ◽

Zeolite Catalysts ◽

Benzene Toluene ◽

Acid Strength Distribution ◽

Silver Cations ◽

Heptane Conversion

The conversion of n-heptanes into aromatic hydrocarbons benzene, toluene and xylenes (BTX), by the chromatographic pulse method in the temperature range of 673 - 823K was performed over the HZSM-5 and Ag-HZSM-5 zeolites modified by ion exchange with AgNO3 aqueous solutions. The catalysts, HZSM-5 (SiO2/Al2O3 = 33.9), and Ag-HZSM-5 (Ag1-HZSM-5 wt. % Ag1.02, Ag2-HZSM-5 wt. % Ag 1.62; and Ag3-HZSM-5 wt. % Ag 2.05 having different acid strength distribution exhibit a conversion and a yield of aromatics depending on temperature and metal content. The yield of aromatic hydrocarbons BTX appreciably increased by incorporating silver cations Ag+ into HZSM-5.

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The effect of composition of cobalt-molybdenum catalysts on their surface acidity and isomerisation activity

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19800697 ◽

1980 ◽

Vol 45 (3) ◽

pp. 697-702 ◽

Cited By ~ 1

Author(s):

Vlastimil Vyskočil ◽

Miroslav Zdražil

Keyword(s):

Chromatographic Method ◽

Surface Acidity ◽

Parallel Reaction ◽

Molybdenum Catalysts ◽

The Difference ◽

Kinetics Of ◽

Alumina Catalysts

Kinetics of isomerisation of cyclohexene to methylcyclopentene proceeding as parallel reaction to hydrogenation of cyclohexene to cyclohexane on cobalt-molybdenum catalysts of different composition has been measured. The surface acidity of these catalysts was estimated from the difference in the adsorption of toluene and heptane which was measured by chromatographic method. In a series of catalysts containing molybdenum the acidity parallels isomerisation activity. Cobalt on alumina catalysts and alumina itself have greater acidity but exhibit lower isomerisation activity compared to the catalysts containing molybdenum.

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