Electronic metal support interaction in platinum catalysts under deuterium-ethene reaction conditions and the microscopic nature of the active sites

1992 ◽  
Vol 96 (3) ◽  
pp. 1329-1334 ◽  
Author(s):  
Hideaki Yoshitake ◽  
Yasuhiro Iwasawa
Keyword(s):  
Active Sites ◽  
Platinum Catalysts ◽  
Reaction Conditions ◽  
Support Interaction ◽  
Metal Support Interaction ◽  
Metal Support

Co-processing of hydrodeoxygenation and hydrodesulfurization of phenol and dibenzothiophene with NiMo/Al2O3–ZrO2 and NiMo/TiO2–ZrO2 catalysts

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Jesús Andrés Tavizón Pozos ◽  
Gerardo Chávez Esquivel ◽  
Ignacio Cervantes Arista ◽  
José Antonio de los Reyes Heredia ◽  
Víctor Alejandro Suárez Toriello
Keyword(s):  
Active Sites ◽  
Reaction Rate ◽  
Supported Catalysts ◽  
Initial Reaction Rate ◽  
Initial Reaction ◽  
Competition Effect ◽  
Support Interaction ◽  
Highly Active ◽  
Metal Support Interaction ◽  
Metal Support

Abstract The influence of Al2O3–ZrO2 and TiO2–ZrO2 supports on NiMo-supported catalysts at a different sulfur concentration in a model hydrodeoxygenation (HDO)-hydrodesulfurization (HDS) co-processing reaction has been studied in this work. A competition effect between phenol and dibenzothiophene (DBT) for active sites was evidenced. The competence for the active sites between phenol and DBT was measured by comparison of the initial reaction rate and selectivity at two sulfur concentrations (200 and 500 ppm S). NiMo/TiO2–ZrO2 was almost four-fold more active in phenol HDO co-processed with DBT than NiMo/Al2O3–ZrO2 catalyst. Consequently, more labile active sites are present on NiMo/TiO2–ZrO2 than in NiMo/Al2O3–ZrO2 confirmed by the decrease in co-processing competition for the active sites between phenol and DBT. DBT molecules react at hydrogenolysis sites (edge and rim) preferentially so that phenol reacts at hydrogenation sites (edge and edge). However, the hydrogenated capacity would be lost when the sulfur content was increased. In general, both catalysts showed similar functionalities but different degrees of competition according to the highly active NiMoS phase availability. TiO2–ZrO2 as the support provided weaker metal-support interaction than Al2O3–ZrO2, generating a larger fraction of easily reducible octahedrally coordinated Mo- and Ni-oxide species, causing that NiMo/TiO2–ZrO2 generated precursors of MoS2 crystallites with a longer length and stacking but with a higher degree of Ni-promotion than NiMo/Al2O3–ZrO2 catalyst.

Strategy for stabilizing noble metal nanoparticles without sacrificing active sites

2019 ◽  
Vol 55 (48) ◽  
pp. 6846-6849 ◽  
Author(s):  
Weikang Ji ◽  
Xuyu Wang ◽  
Minni Tang ◽  
Le Yang ◽  
Zebao Rui ◽  
...  
Keyword(s):  
Metal Nanoparticles ◽  
Noble Metal ◽  
Active Sites ◽  
Noble Metal Nanoparticles ◽  
Electronic Interaction ◽  
Pt Nanoparticle ◽  
Support Interaction ◽  
Metal Support Interaction ◽  
Metal Support ◽  
Surface Fluorination

We report a facile surface fluorination strategy for restricting Pt nanoparticle sintering through providing anchoring sites on the TiO2 support and enhancing metal–support interaction via improved electronic interaction without sacrificing the active sites.

scholarly journals The role of metal–support interaction for CO-free hydrogen from low temperature ethanol steam reforming on Rh–Fe catalysts

2017 ◽  
Vol 19 (6) ◽  
pp. 4199-4207 ◽  
Author(s):  
Catherine K. S. Choong ◽  
Luwei Chen ◽  
Yonghua Du ◽  
Martin Schreyer ◽  
S. W. Daniel Ong ◽  
...  
Keyword(s):  
Steam Reforming ◽  
Active Sites ◽  
Support Interaction ◽  
Metal Support Interaction ◽  
Free Hydrogen ◽  
Metal Support ◽  
Fe Catalysts ◽  
Ethanol Steam

Effect of metal–support interaction on the generation of Rh–FexOy active sites is investigated via various in situ techniques.

scholarly journals Tuning Metal–Support Interactions on Ni/Al2O3 Catalysts to Improve Catalytic Activity and Stability for Dry Reforming of Methane

Processes ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 706
Author(s):  
Lulu He ◽  
Yuanhang Ren ◽  
Bin Yue ◽  
Shik Chi Edman Tsang ◽  
Heyong He
Keyword(s):  
Calcination Temperature ◽  
Active Sites ◽  
Dry Reforming ◽  
Dry Reforming Of Methane ◽  
Impregnation Method ◽  
Nickel Aluminate ◽  
Support Interaction ◽  
Metal Support Interaction ◽  
Metal Support ◽  
Crystallite Sizes

Ni-based catalysts supported on alumina derived from the pseudo-boehmite prepared by the impregnation method were employed for catalytic dry reforming of methane reaction at the temperature of 550–750 °C. The effect of calcination temperature on physicochemical properties such as the Ni dispersion, reduction degree, nickel crystallite sizes, and metal–support interaction of the catalysts was investigated. The characterization results show that increasing the catalyst calcination temperature leads to the formation of nickel-alumina spinel, which enhances the metal–support interaction and increases the reduction temperature. The nickel nanoparticle size decreases and the effective dispersion increases with the increasing calcination temperature from 450 °C to 750 °C due to the formation of nickel aluminate. The catalyst calcined at 750 °C exhibits the highest CH4 and CO2 conversion owing to the small Ni0 active sites and high Ni dispersion. In a 200 h stability test in dry reforming of methane at 700 °C, the Ni/Al2O3-750 catalyst exhibits excellent catalytic stability and anti-coking ability.

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