scholarly journals Large Ferrierite Crystals as Models for Catalyst Deactivation during Skeletal Isomerisation of Oleic Acid: Evidence for Pore Mouth Catalysis

2015 ◽  
Vol 22 (1) ◽  
pp. 199-210 ◽  
Author(s):  
Sophie C. C. Wiedemann ◽  
Zoran Ristanović ◽  
Gareth T. Whiting ◽  
V. R. Reddy Marthala ◽  
Jörg Kärger ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Catalyst Deactivation ◽  
Skeletal Isomerisation ◽  
Pore Mouth

Skeletal isomerisation of oleic acid over ferrierite in the presence and absence of triphenylphosphine: Pore mouth catalysis and related deactivation mechanisms

2014 ◽  
Vol 316 ◽  
pp. 24-35 ◽  
Author(s):  
Sophie C.C. Wiedemann ◽  
Joseph A. Stewart ◽  
Fouad Soulimani ◽  
Tanja van Bergen-Brenkman ◽  
Stephan Langelaar ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Skeletal Isomerisation ◽  
Pore Mouth ◽  
Presence And Absence

scholarly journals Skeletal isomerisation of oleic acid over ferrierite: Influence of acid site number, accessibility and strength on activity and selectivity

2015 ◽  
Vol 329 ◽  
pp. 195-205 ◽  
Author(s):  
Sophie C.C. Wiedemann ◽  
Ara Muñoz-Murillo ◽  
Ramon Oord ◽  
Tanja van Bergen-Brenkman ◽  
Bas Wels ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Acid Site ◽  
Site Number ◽  
Skeletal Isomerisation

Catalyst Deactivation through Pore Mouth Plugging during Residue Desulfurization

1978 ◽  
pp. 254-267 ◽  
Author(s):  
F. M. DAUTZENBERG ◽  
J. VAN KLINKEN ◽  
K. M. A. PRONK ◽  
S. T. SIE ◽  
J-B. WIJFFELS
Keyword(s):  
Catalyst Deactivation ◽  
Pore Mouth

What catalysis needs from the electron microscopist

1988 ◽  
Vol 46 ◽  
pp. 694-695
Author(s):  
Alexis T. Bell
Keyword(s):  
Active Sites ◽  
Heterogeneous Catalysts ◽  
Catalyst Deactivation ◽  
Surface Composition ◽  
Internal Surface ◽  
Active Phase ◽  
Atomic Scale ◽  
Metal Catalyst ◽  
Internal Surface Area ◽  
Porous Support

Heterogeneous catalysts, used in industry for the production of fuels and chemicals, are microporous solids characterized by a high internal surface area. The catalyticly active sites may occur at the surface of the bulk solid or of small crystallites deposited on a porous support. An example of the former case would be a zeolite, and of the latter, a supported metal catalyst. Since the activity and selectivity of a catalyst are known to be a function of surface composition and structure, it is highly desirable to characterize catalyst surfaces with atomic scale resolution. Where the active phase is dispersed on a support, it is also important to know the dispersion of the deposited phase, as well as its structural and compositional uniformity, the latter characteristics being particularly important in the case of multicomponent catalysts. Knowledge of the pore size and shape is also important, since these can influence the transport of reactants and products through a catalyst and the dynamics of catalyst deactivation.

A magnetic super lattice

1987 ◽  
Vol 45 ◽  
pp. 360-361 ◽  
Author(s):  
M.D. Bentzon ◽  
J. v. Wonterghem ◽  
A. Thölén
Keyword(s):  
Thermal Decomposition ◽  
Oleic Acid ◽  
Magnetic Fluid ◽  
Magnetic Particles ◽  
Carbon Film ◽  
Thick Layer ◽  
Amorphous Iron ◽  
Super Lattice ◽  
Carrier Liquid ◽  
Median Diameter

We report on the oxidation of a magnetic fluid. The oxidation results in magnetic super lattice crystals. The “atoms” are hematite (α-Fe2O3) particles with a diameter ø = 6.9 nm and they are covered with a 1-2 nm thick layer of surfactant molecules.Magnetic fluids are homogeneous suspensions of small magnetic particles in a carrier liquid. To prevent agglomeration, the particles are coated with surfactant molecules. The magnetic fluid studied in this work was produced by thermal decomposition of Fe(CO)5 in Declin (carrier liquid) in the presence of oleic acid (surfactant). The magnetic particles consist of an amorphous iron-carbon alloy. For TEM investigation a droplet of the fluid was added to benzine and a carbon film on a copper net was immersed. When exposed to air the sample starts burning. The oxidation and electron irradiation transform the magnetic particles into hematite (α-Fe2O3) particles with a median diameter ø = 6.9 nm.

Analytical Electron Microscopy study of two vehicle-aged automotive exhaust catalysts having dissimilar activities

1989 ◽  
Vol 47 ◽  
pp. 272-273
Author(s):  
Sooho Kim ◽  
M. J. D’Aniello
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Noble Metal ◽  
Catalyst Deactivation ◽  
Analytical Electron Microscopy ◽  
Microscopy Study ◽  
Metal Particles ◽  
Automotive Exhaust ◽  
Exhaust Catalysts ◽  
Analytical Electron

Automotive catalysts generally lose-agtivity during vehicle operation due to several well-known deactivation mechanisms. To gain a more fundamental understanding of catalyst deactivation, the microscopic details of fresh and vehicle-aged commercial pelleted automotive exhaust catalysts containing Pt, Pd and Rh were studied by employing Analytical Electron Microscopy (AEM). Two different vehicle-aged samples containing similar poison levels but having different catalytic activities (denoted better and poorer) were selected for this study.The general microstructure of the supports and the noble metal particles of the two catalysts looks similar; the noble metal particles were generally found to be spherical and often faceted. However, the average noble metal particle size on the poorer catalyst (21 nm) was larger than that on the better catalyst (16 nm). These sizes represent a significant increase over that found on the fresh catalyst (8 nm). The activity of these catalysts decreases as the observed particle size increases.

An analytical microscopic study of metals in fluidized catalytic cracking catalyst

1986 ◽  
Vol 44 ◽  
pp. 854-855
Author(s):  
Clifford S. Rainey
Keyword(s):  
Electron Microscopy ◽  
Spatial Distribution ◽  
Catalytic Cracking ◽  
Catalyst Deactivation ◽  
Coke Formation ◽  
Acid Sites ◽  
Y Zeolite ◽  
Fcc Catalyst ◽  
Fluidized Catalytic Cracking ◽  
High Regeneration

The spatial distribution of V and Ni deposited within fluidized catalytic cracking (FCC) catalyst is studied because these metals contribute to catalyst deactivation. Y zeolite in FCC microspheres are high SiO2 aluminosilicates with molecular-sized channels that contain a mixture of lanthanoids. They must withstand high regeneration temperatures and retain acid sites needed for cracking of hydrocarbons, a process essential for efficient gasoline production. Zeolite in combination with V to form vanadates, or less diffusion in the channels due to coke formation, may deactivate catalyst. Other factors such as metal "skins", microsphere sintering, and attrition may also be involved. SEM of FCC fracture surfaces, AEM of Y zeolite, and electron microscopy of this work are developed to better understand and minimize catalyst deactivation.

Intestinal Absorption of Iodine131-Labeled Triolein and Oleic Acid in Normal Subjects and in Steatorrhea

1958 ◽  
Vol 34 (5) ◽  
pp. 901-909 ◽  
Author(s):  
Ervin Kaplan ◽  
Bernard D. Edidin ◽  
Robert C. Fruin ◽  
Lyle A. Baker
Keyword(s):  
Oleic Acid ◽  
Intestinal Absorption ◽  
Normal Subjects

Oleic acid

2015 ◽  
Author(s):  
LB Becnel ◽  
YF Darlington ◽  
S Orechsner ◽  
J Easton-Marks ◽  
CA Watkins ◽  
...  
Keyword(s):  
Oleic Acid

Reusability Study of Sulfated Zirconia Functionalized SBA-15 Catalyst for Biolubricant Oil Production from Oleic Acid

2019 ◽  
Vol 1 (1) ◽  
pp. 46
Author(s):  
F R Rangganita ◽  
L Hermida ◽  
A Angraeni ◽  
D Khoirunnisa
Keyword(s):  
Oleic Acid ◽  
Sulfated Zirconia ◽  
Room Temperature ◽  
Oil Production ◽  
Catalyst Reusability

Sulfated zirconia functionalized SBA-15 catalsyt (SZr-SBA-15) was prepared byreacting SBA-15 with Zirkoniumoxychloride and urea at 90oC to form ZrO2-SBA-15. Then, ZrO2-SBA-15 was reacted with H2SO4 at room temperature to produceSZr-SBA-15 catalsyt.. The catalyst was characterized in terms of adsorptiondesorption nitrogen analysis, SEM-EDX and FTIR. Based on SEM-EDX andadsorption-desorption nitrogen analysis results, it was found that Zr had beenincorporated in SBA-15. By using the SZr-SBA-15 catalyst, esterification reactionof oleic acid with TMP to produce biolubricant oil of Trimethylolpropanetrioleatachieved 85% oleic acid conversion and selectivity of 63,7%. Reusability study ofSZr-SBA-15 catalyst was carried out for 3 rounds of reaction. It was found that thecatalyst could be used up to 3 rounds without significant decrease in activityKeywords: biolubricant oil, catalyst reusability, sba-15, sulfated zirconia.

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