scholarly journals Development of Pt/WO3-ZrO2-Al2O3 Catalyst for Isomerization of Normal Heptane (Part 1) Control of Catalyst Acidity to Improve Isomerization Selectivity

2007 ◽  
Vol 50 (6) ◽  
pp. 312-321
Author(s):  
Koichi Matsushita ◽  
Makoto Oyamada ◽  
Satoshi Aramaki
Keyword(s):  
Isomerization Selectivity ◽  
Catalyst Acidity

Effect of Catalyst Acidity and Reaction Temperature on Hexene Cracking Reaction to Produce Propylene

2021 ◽  
Vol 35 (4) ◽  
pp. 3295-3306
Author(s):  
Hailing Sun ◽  
Liyuan Cao ◽  
Yuhao Zhang ◽  
Liang Zhao ◽  
Jinsen Gao ◽  
...  
Keyword(s):  
Reaction Temperature ◽  
Cracking Reaction ◽  
Catalyst Acidity

scholarly journals Co-loading of Pt and Fe on *BEA Zeolite for Enhanced Isomerization Selectivity in n-Heptane Conversion

2018 ◽  
Vol 47 (11) ◽  
pp. 1428-1430
Author(s):  
Ryosuke Ushiki ◽  
Yoshinori Akada ◽  
Masahiko Matsukata
Keyword(s):  
Bea Zeolite ◽  
Isomerization Selectivity ◽  
Heptane Conversion

scholarly journals The role of catalyst acidity and shape selectivity on products from the catalytic fast pyrolysis of beech wood

2019 ◽  
pp. 104710 ◽  
Author(s):  
Joseph Socci ◽  
Alireza Saraeian ◽  
Stylianos D. Stefanidis ◽  
Scott W. Banks ◽  
Brent H. Shanks ◽  
...  
Keyword(s):  
Beech Wood ◽  
Fast Pyrolysis ◽  
Shape Selectivity ◽  
Catalytic Fast Pyrolysis ◽  
Catalyst Acidity

scholarly journals Determination of Catalyst Surface Acidity in Liquids by a Pulse Liquid Chromatographic Technique

2005 ◽  
Vol 23 (9) ◽  
pp. 739-749 ◽  
Author(s):  
Paolo Carniti ◽  
Antonella Gervasini ◽  
Serena Biella
Keyword(s):  
Surface Acidity ◽  
Lower Amount ◽  
Chromatographic Technique ◽  
Solvent Flow Rate ◽  
Acidic Sites ◽  
Catalyst Acidity ◽  
Set Up ◽  
Liquid Chromatographic

A pulse liquid chromatographic technique, set up by using an HPLC apparatus, is proposed for the characterization of the surface acidity of solid acids in liquids in view of their use as catalysts in liquid–solid reactions. Dosed amounts of solutions of two different basic probe molecules (2-phenylethylamine, pKa = 9.84 and aniline, pKa = 4.63) in solvents of different polarity were injected onto solid samples (acidic resins, Amberlites and a mixed silica–zirconia oxide) at a constant solvent flow rate. Titration with the weakest basic probe (aniline) rather than 2-phenylethylamine generally led to a lower amount of acidic sites. The amount of acidic sites determined at the surface was greatly affected by the solvent. With silica–zirconia, a higher amount of acidic sites was established by titration in apolar rather than polar solvents. The results have been compared with those obtained by conventional methods, i.e. ion exchange employing salts and, for silica–zirconia, Hammett titrations. The quite satisfactory results obtained are of some importance in establishing valuable relationships between catalyst acidity and catalytic activity in various solvents.

scholarly journals Toward Understanding of the Effect of Nucleation Temperature on Porous Structure of Micro-Mesoporous Composite Molecular Sieves and Related Crystallization Mechanism

Catalysts ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 777 ◽  
Author(s):  
Chunwei Shi ◽  
Jingjing Liu ◽  
Wenyuan Wu ◽  
Xue Bian ◽  
Ping Chen ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Porous Structure ◽  
Molecular Sieves ◽  
Crystallization Mechanism ◽  
Nucleation Temperature ◽  
X Ray Diffraction ◽  
Mesoporous Composite ◽  
Transmission Electron ◽  
Isomerization Selectivity ◽  
Crystal Particle

Although micro-mesoporous composite molecular sieves have received significant attention due to their desirable properties, they still lack systematic studies on their crystallization process to achieve controllable synthesis of composite molecular sieves. In this study, a series of Y/SBA-15 micro-mesoporous composite molecular sieves with different porous structures were synthesized by tuning nucleation temperature, based on epitaxial growth on the outer surface of the Y-type crystal particle. All composite molecular sieves were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscope (TEM). Moreover, the effect of nucleation temperature on the structure of composite molecular sieves was investigated, while the crystallization mechanism was also explored. Furthermore, the performance of the molecular sieves on isomerization of n-pentane was investigated, the results suggested that the isomerization selectivity was positively correlated with regularity degree of the mesoporous porous structure, where the highest isomerization reached 95.81%. This work suggests that nucleation temperature plays a key role in structures of micro-mesoporous composite molecular sieves, providing a solid basis for the further development of functional composite molecular sieves.

Catalytic Activity and Physical Properties of Nanoparticles Metal Supported on Bentonite for Hydrogenolysis of Glycerol

2011 ◽  
Vol 364 ◽  
pp. 211-216
Author(s):  
Noraini Hamzah ◽  
Wan Nor Roslam Wan Isahak ◽  
Nadia Farhana Adnan ◽  
Nor Asikin Mohamad Nordin ◽  
Mohamad Bin Kassim ◽  
...  
Keyword(s):  
High Activity ◽  
Hydrogen Pressure ◽  
Au Nanoparticles ◽  
Catalyst System ◽  
Impregnation Method ◽  
Tem Analysis ◽  
Glycerol Hydrogenolysis ◽  
Initial Hydrogen Pressure ◽  
Catalyst Acidity ◽  
Average Size

Catalysts prepared from a variety of noble metal (Os, Ru, Pd and Au) supported on bentonite using impregnation method were studied and it found these series catalyst system gave different activity and selectivity. Among these catalysts, Os/bentonite and Ru/bentonite catalyst showed high activity in glycerol hydrogenolysis reaction at 150°C, 2.0 MPa initial hydrogen pressure for 7 hours. TEM analysis revealed that these nanometal particles catalyst have different in size and result showed that Os and Ru which have smaller average size in range 1-3 nm gave high activity which are 54.1% and 61.2% respectively. In contrast, less activity was obtained when using Pd/bentonite (29.0%) and Au/bentonite (27.8%) catalyst and TEM result showed that Pd and Au nanoparticles have large average particles size (8-10) nm. NH3-TPD analysis revealed that Ru/bentonite and Os/bentonite catalyst gave high total acidity and this behaviour contribute to high activity of the catalyst. This study revealed that size of nanoparticles and catalyst acidity play an important role in the activity and selectivity in glycerol hydrogenolysis reaction. These catalysts were also characterized by BET, XRD and XPS in order to get some physicochemical properties of the catalyst.

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