A Cooperative OSDA Blueprint for Highly Siliceous Faujasite Zeolite Catalysts with Enhanced Acidity Accessibility

As with all techniques which are relatively new and therefore underutilized, diamond knife sectioning in the physical sciences continues to see both developments of the technique and novel applications.Technique Developments Development of specific orientation/embedding procedures for small pieces of awkward shape is exemplified by the work of Bradley et al on large, rather fragile particles of nuclear waste glass. At the same time, the frequent problem of pullout with large particles can be reduced by roughening of the particle surface, and a proven methodology using a commercial coupling agent developed for glasses has been utilized with good results on large zeolite catalysts. The same principle (using acid etches) should work for ceramic fibres or metal wires which may only partially pull out but result in unacceptably thick sections. Researchers from the life sciences continue to develop aspects of embedding media which may be applicable to certain cases in the physical sciences.

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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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Selective Production of Aromatics from 2-Octanol on Zinc Ion-Exchanged MFI Zeolite Catalysts

Catalysts ◽

10.3390/catal5042122 ◽

2015 ◽

Vol 5 (4) ◽

pp. 2122-2133 ◽

Cited By ~ 2

Author(s):

Masakazu Iwamoto ◽

Ryota Takezawa ◽

Masao Morimoto

Keyword(s):

Zinc Ion ◽

Zeolite Catalysts ◽

Mfi Zeolite

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Synthesis of Renewable Diesel through Hydrodeoxygenation Using Pd/zeolite Catalysts

Procedia Chemistry ◽

10.1016/j.proche.2014.05.017 ◽

2014 ◽

Vol 9 ◽

pp. 139-150 ◽

Cited By ~ 11

Author(s):

Bambang Heru Susanto ◽

Mohammad Nasikin ◽

Sukirno ◽

Andri Wiyo

Keyword(s):

Zeolite Catalysts ◽

Renewable Diesel

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Effect of synthesis and activation methods on the character of CoMo/ultrastable Y-zeolite catalysts

Open Chemistry ◽

10.1515/chem-2021-0064 ◽

2021 ◽

Vol 19 (1) ◽

pp. 745-754

Author(s):

Khoirina Dwi Nugrahaningtyas ◽

Eddy Heraldy ◽

Rachmadani ◽

Yuniawan Hidayat ◽

Indriana Kartini

Keyword(s):

Electron Microscopy ◽

Reduction Process ◽

Particle Morphology ◽

Zeolite Catalysts ◽

X Ray Diffraction ◽

Y Zeolite ◽

X Ray ◽

Irregular Particle ◽

Transmission Electron ◽

Pure Metals

Abstract The properties of three types of CoMo/USY catalysts with different synthesized methods have been studied. The sequential and co-impregnation methods followed by activation using calcination and reduction process have been conducted. The properties of the catalysts were examined using Fourier-transform-infrared (FTIR) spectroscopy, X-ray diffraction (XRD) with refinement, and surface area analyzer (SAA). The FTIR spectrum study revealed the enhanced intensity of its Bronsted acid site, and the XRD diffractogram pattern verified the composition of pure metals, oxides, and alloys in the catalyst. The SAA demonstrated the mesoporous features of the catalyst. Scanning electron microscopy showed an irregular particle morphology. Additional analysis using the transmission electron microscopy indicated that the metal has successfully impregnated without damaging the USY structure.

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Progress and future challenges in passive NO adsorption over Pd/zeolite catalysts

Catalysis Science & Technology ◽

10.1039/d1cy01084k ◽

2021 ◽

Author(s):

Guohua Jing ◽

Johannes W. Schwank ◽

Alexander J Hill ◽

Huawang Zhao ◽

Lei Ma ◽

...

Keyword(s):

Cold Start ◽

Zeolite Catalysts ◽

Catalytic Converters ◽

No Adsorption ◽

Emission Standards ◽

Future Challenges ◽

Future Emission

Future emission standards are becoming increasingly stringent. Around 50% of targeted tailpipe emissions are emitted during the cold-start period, mainly due to the ineffectiveness of catalytic converters in the after-treatment...

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