Effect of the mechanical activation of a mixture of MnCO3 · mMn(OH)2 · nH2O and AlOOH as a stage of the preparation of a MnO x -Al2O3 catalyst on its phase composition and catalytic activity in CO oxidation

The concept of very strong metal–support interactions (VSMSI) was defined in regard to the interactions that influence the catalytic properties of catalysts due to the creation of a new phase as a result of a solid-state chemical reaction between the metal and support. In this context, the high catalytic activity of the 1%Pt/Al2O3 catalyst in the CO oxidation reaction at room temperature was explained. The catalyst samples were reduced at different temperatures ranging from 500 °C to 800 °C and characterized using TPR, O2/H2 titration, CO chemisorption, TPD-CO, FTIR-CO, XRD, and TOF-SIMS methods. Based on the obtained results, it was claimed that with very high temperature reduction (800 °C), nonstoichiometric platinum species [Pt(Cl)Ox] strongly anchored to Al2O3 surface are formed. These species act as the oxygen adsorption sites.

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Effect of phase composition between nano γ- and χ-Al2O3 on Pt/Al2O3 catalyst in CO oxidation

Catalysis Communications ◽

10.1016/j.catcom.2007.04.016 ◽

2008 ◽

Vol 9 (4) ◽

pp. 546-550 ◽

Cited By ~ 48

Author(s):

Chatchai Meephoka ◽

Choowong Chaisuk ◽

Panida Samparnpiboon ◽

Piyasan Praserthdam

Keyword(s):

Phase Composition ◽

Co Oxidation ◽

Al2o3 Catalyst

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Observation of Increased Dispersion of Pt and Mobility of Oxygen in Pt/g-Al2O3 Catalyst with La Modification in CO Oxidation

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.14.3.4518.579-585 ◽

2019 ◽

Vol 14 (3) ◽

pp. 579

Author(s):

Thanawat Wandondaeng ◽

Chaowat Autthanit ◽

Bunjerd Jongsomjit ◽

Piyasan Praserthdam

Keyword(s):

Catalytic Activity ◽

Co Oxidation ◽

Surface Coverage ◽

Molar Ratio ◽

Oxygen Mobility ◽

Molar Ratios ◽

La Addition ◽

Temperature Programmed ◽

La Modification ◽

Al2o3 Catalyst

The study focuses on an improvement of the catalytic activity via CO oxidation for Pt/g-Al2O3 catalyst by addition of La onto the support prior to impregnation with Pt metals. The molar ratios of La/Al were varied from 0.01 to 0.15. Based on temperature-programmed desorption (TPD) of CO2, La addition apparently resulted in increased basicity of the catalysts, which is related to increasing of oxygen mobility. However, when considered the Pt dispersion measured by CO chemisorption, it was found that Pt dispersion also increased with increasing the amount of La addition up to La/Al = 0.05. It is suggested that too high amount of La addition can inhibit the dispersion Pt due to surface coverage of La. It is worth noting that the catalytic activity toward CO oxidation essentially depends on both Pt dispersion and oxygen mobility and they can be superimposed on each other. Based on this study, the Pt/g-Al2O3 catalyst with La addition of La/Al molar ratio = 0.05 showed the highest activity due to its optimal Pt dispersion and oxygen mobility leading to its highest value of turnover frequency (TOF). Copyright © 2019 BCREC Group. All rights reserved

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A novel Pd3O9@α-Al2O3 catalyst under a hydroxylated effect: high activity in the CO oxidation reaction

Physical Chemistry Chemical Physics ◽

10.1039/c5cp03740a ◽

2015 ◽

Vol 17 (48) ◽

pp. 32140-32148 ◽

Cited By ~ 3

Author(s):

Qiaohong Li ◽

Yongqin Wei ◽

Rongjian Sa ◽

Zuju Ma ◽

Kechen Wu

Keyword(s):

Catalytic Activity ◽

Co Oxidation ◽

High Activity ◽

Oxidation Reaction ◽

Co Oxidation Reaction ◽

Α Al2o3 ◽

Al2o3 Catalyst

A new Pd3O9@α-Al2O3 catalyst has been designed which shows superior catalytic activity for CO oxidation.

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Nanosized Oxide Materials: Morphology, Phase Composition and Catalytic Activity in CO Oxidation

2020 IEEE 40th International Conference on Electronics and Nanotechnology (ELNANO) ◽

10.1109/elnano50318.2020.9088830 ◽

2020 ◽

Author(s):

Larisa Lutsenko ◽

Luidmila Oleksenko ◽

Inna Vasylenko ◽

Olexander Ripko ◽

George Fedorenko ◽

...

Keyword(s):

Catalytic Activity ◽

Phase Composition ◽

Co Oxidation ◽

Oxide Materials ◽

Nanosized Oxide

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CO Oxidation Efficiency and Hysteresis Behavior over Mesoporous Pd/SiO2 Catalyst

Catalysts ◽

10.3390/catal11010131 ◽

2021 ◽

Vol 11 (1) ◽

pp. 131 ◽

Cited By ~ 1

Author(s):

Rola Mohammad Al Soubaihi ◽

Khaled Mohammad Saoud ◽

Myo Tay Zar Myint ◽

Mats A. Göthelid ◽

Joydeep Dutta

Keyword(s):

Carbon Monoxide ◽

Catalytic Activity ◽

Co Oxidation ◽

Active Sites ◽

Bond Activation ◽

Dissociative Adsorption ◽

High Catalytic Activity ◽

Good Catalytic Activity ◽

Pretreatment Conditions ◽

Oxidation Efficiency

Carbon monoxide (CO) oxidation is considered an important reaction in heterogeneous industrial catalysis and has been extensively studied. Pd supported on SiO2 aerogel catalysts exhibit good catalytic activity toward this reaction owing to their CO bond activation capability and thermal stability. Pd/SiO2 catalysts were investigated using carbon monoxide (CO) oxidation as a model reaction. The catalyst becomes active, and the conversion increases after the temperature reaches the ignition temperature (Tig). A normal hysteresis in carbon monoxide (CO) oxidation has been observed, where the catalysts continue to exhibit high catalytic activity (CO conversion remains at 100%) during the extinction even at temperatures lower than Tig. The catalyst was characterized using BET, TEM, XPS, TGA-DSC, and FTIR. In this work, the influence of pretreatment conditions and stability of the active sites on the catalytic activity and hysteresis is presented. The CO oxidation on the Pd/SiO2 catalyst has been attributed to the dissociative adsorption of molecular oxygen and the activation of the C-O bond, followed by diffusion of adsorbates at Tig to form CO2. Whereas, the hysteresis has been explained by the enhanced stability of the active site caused by thermal effects, pretreatment conditions, Pd-SiO2 support interaction, and PdO formation and decomposition.

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On the Effects of Doping on the Catalytic Performance of (La,Sr)CoO3. A DFT Study of CO Oxidation

Catalysts ◽

10.3390/catal9040312 ◽

2019 ◽

Vol 9 (4) ◽

pp. 312 ◽

Cited By ~ 2

Author(s):

Antonella Glisenti ◽

Andrea Vittadini

Keyword(s):

Catalytic Activity ◽

Co Oxidation ◽

Density Functional Calculations ◽

Density Functional ◽

Formation Energy ◽

Oxygen Vacancies ◽

Catalytic Performance ◽

Energy Profiles ◽

High Concentrations ◽

3D Impurities

The effects of modifying the composition of LaCoO3 on the catalytic activity are predicted by density functional calculations. Partially replacing La by Sr ions has benefical effects, causing a lowering of the formation energy of O vacancies. In contrast to that, doping at the Co site is less effective, as only 3d impurities heavier than Co are able to stabilize vacancies at high concentrations. The comparison of the energy profiles for CO oxidation of undoped and of Ni-, Cu-m and Zn-doped (La,Sr)CoO3(100) surface shows that Cu is most effective. However, the effects are less spectacular than in the SrTiO3 case, due to the different energetics for the formation of oxygen vacancies in the two hosts.

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