Effect of the acidity of HZSM-5/MCM-41 hierarchical zeolite on its catalytic performance in supercritical catalytic cracking ofn-dodecane: experiments and mechanism

Manganese catalysts containing templated mesostructured porous silica were prepared using different methods of preparation, namely, the direct hydrothermal (DHT), solid-state ion exchange (SSI), template ion exchange (TIE), and impregnation (Imp) methods. The physical-chemical properties of materials were characterized by X-ray diffraction (XRD), N2 adsorption-desorption, FT-IR, TEM, EDX, UV-Vis, EPR, and H2 TPR techniques. The results of this study indicate that the obtained catalysts retained their hexagonal mesopore structure after introducing Mn into MCM-41. On the contrary, the crystalline phase of manganese oxide was stabilized on the external surface and inside the mesoporosity of the MCM-41 and seems to be dependent on the synthesis method used. Catalytic performances of synthesized materials were then investigated in methane oxidation at atmospheric pressure. The results showed that the metal loading and catalysts synthesis procedure influence the catalytic performance of the obtained materials. Moreover, the activity of the catalyst depends on the crystalline phase and particularly on the environment of the active phase.

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Enhanced catalytic performance in low-temperature NH3-SCR process of spherical MCM-41 modified with Cu by template ion-exchange and ammonia treatment

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2021.110920 ◽

2021 ◽

Vol 315 ◽

pp. 110920

Author(s):

Aleksandra Jankowska ◽

Agata Chłopek ◽

Andrzej Kowalczyk ◽

Małgorzata Rutkowska ◽

Włodzimierz Mozgawa ◽

...

Keyword(s):

Low Temperature ◽

Ion Exchange ◽

Catalytic Performance ◽

Ammonia Treatment ◽

Nh3 Scr ◽

Mcm 41

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The design and catalytic performance of molybdenum active sites on an MCM-41 framework for the aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

Catalysis Science & Technology ◽

10.1039/c8cy02291g ◽

2019 ◽

Vol 9 (3) ◽

pp. 811-821 ◽

Cited By ~ 7

Author(s):

Zhao-Meng Wang ◽

Li-Juan Liu ◽

Bo Xiang ◽

Yue Wang ◽

Ya-Jing Lyu ◽

...

Keyword(s):

Catalytic Activity ◽

Active Sites ◽

Aerobic Oxidation ◽

Catalytic Performance ◽

Mcm 41

The catalytic activity decreases as –(SiO)3Mo(OH)(O) > –(SiO)2Mo(O)2 > –(O)4–MoO.

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Catalytic cracking of jatropha oil into biofuel over hierarchical zeolite supported NiMo catalyst

10.1063/5.0051737 ◽

2021 ◽

Author(s):

Isalmi Aziz ◽

Tri Retnaningsih ◽

Dhika Gustama ◽

Nanda Saridewi ◽

Lisa Adhani ◽

...

Keyword(s):

Catalytic Cracking ◽

Jatropha Oil ◽

Hierarchical Zeolite ◽

Nimo Catalyst

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A diffusion anisotropy descriptor links morphology effects of H-ZSM-5 zeolites to their catalytic cracking performance

Communications Chemistry ◽

10.1038/s42004-021-00543-w ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Xiaoliang Liu ◽

Jing Shi ◽

Guang Yang ◽

Jian Zhou ◽

Chuanming Wang ◽

...

Keyword(s):

Catalytic Activity ◽

Catalytic Cracking ◽

Catalytic Performance ◽

Zeolite Catalysts ◽

Time Resolved ◽

Cracking Performance ◽

Morphology Effect ◽

Ft Ir ◽

The Difference ◽

Dynamics Simulations

AbstractZeolite morphology is crucial in determining their catalytic activity, selectivity and stability, but quantitative descriptors of such a morphology effect are challenging to define. Here we introduce a descriptor that accounts for the morphology effect in the catalytic performances of H-ZSM-5 zeolite for C4 olefin catalytic cracking. A series of H-ZSM-5 zeolites with similar sheet-like morphology but different c-axis lengths were synthesized. We found that the catalytic activity and stability is improved in samples with longer c-axis. Combining time-resolved in-situ FT-IR spectroscopy with molecular dynamics simulations, we show that the difference in catalytic performance can be attributed to the anisotropy of the intracrystalline diffusive propensity of the olefins in different channels. Our descriptor offers mechanistic insight for the design of highly effective zeolite catalysts for olefin cracking.

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Preparation of the WOX/MCM-41 Solid Acid Catalyst and the Catalytic Performance for Solketal Synthesis

ACS Omega ◽

10.1021/acsomega.0c05671 ◽

2021 ◽

Vol 6 (5) ◽

pp. 3875-3883

Author(s):

Yixuan Huang ◽

Guangcai Zhang ◽

Qinhui Zhang

Keyword(s):

Solid Acid ◽

Solid Acid Catalyst ◽

Acid Catalyst ◽

Catalytic Performance ◽

Mcm 41

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Diffusion in Fluid Catalytic Cracking Catalysts on Various Displacement Scales and Its Role in Catalytic Performance

Chemistry of Materials ◽

10.1021/cm050031z ◽

2005 ◽

Vol 17 (9) ◽

pp. 2466-2474 ◽

Cited By ~ 56

Author(s):

P. Kortunov ◽

S. Vasenkov ◽

J. Kärger ◽

M. Fé Elía ◽

M. Perez ◽

...

Keyword(s):

Catalytic Cracking ◽

Catalytic Performance ◽

Fluid Catalytic Cracking ◽

Cracking Catalysts

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Preparation of Immobilized Chromium Schiff Base Complexes and their Catalytic Performance for Olefins Epoxidation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.692.240 ◽

2014 ◽

Vol 692 ◽

pp. 240-244

Author(s):

Gong De Wu ◽

Xiao Li Wang ◽

Zhi Li Zhai

Keyword(s):

Hydrogen Peroxide ◽

Schiff Base ◽

Elemental Analysis ◽

Catalytic Performance ◽

Schiff Base Complexes ◽

Metal Centers ◽

Chemical Measurements ◽

Physico Chemical ◽

Immobilized Complexes ◽

Mcm 41

A series of transition metal alanine-salicylaldehyde Schiff base chromium (III) complexes immobilized on MCM-41 were prepared and characterized by various physico-chemical measurements such as FIIR, XRD, HRTEM, N2 sorption and elemental analysis. The immobilized complexes were effective and stable catalysts for the epoxidation of styrene and cyclohexene with 30% hydrogen peroxide. Moreover, the metal centers were found to play important roles in the catalytic performance of immobilized complex catalysts.

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