NiGa Unsupported Catalyst for CO2 Hydrogenation at Atmospheric Pressure. Tentative Reaction Pathways

Here, we report, for the first time, on the catalytic hydrogenation of CO2 to methane at atmospheric pressure. For the preparation of hydrogenation catalysts based on Ni and Fe metals, a convenient method is developed. According to this method, low-temperature reduction of the co-precipitated Ni and Fe oxides with hydrogen gives the effective and selective bimetallic Ni[Formula: see text]Fe[Formula: see text], Ni[Formula: see text]Fe[Formula: see text] and Ni[Formula: see text]Fe[Formula: see text] catalysts. At the temperature range of 300–400[Formula: see text]C, they exhibit a high efficiency of CH4 production with respect to monometallic Ni and Fe catalysts. The results imply a synergistic effect between Ni and Fe which caused the superior activity of the Ni[Formula: see text]Fe[Formula: see text] catalyst conversing [Formula: see text]% of CO2 into CH4 at 350[Formula: see text]C. To adapt the Ni–Fe catalysts in the industry, the effect of two different carriers on the efficiency of the alumina-supported Ni[Formula: see text]Fe[Formula: see text] catalyst was investigated. It is found that the Ni[Formula: see text]Fe[Formula: see text]/[Formula: see text]-Al2O3 catalyst effectively conversed CO2 giving 100% methane yield already at 275[Formula: see text]C.

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Revisiting Catalytic Cycles: A Broader View Through the Energy Span Model

10.26434/chemrxiv.12375047 ◽

2020 ◽

Author(s):

Diego Garay-Ruiz ◽

Carles Bo

Keyword(s):

Catalytic Reaction ◽

Reaction Mechanisms ◽

Computational Study ◽

Reaction Network ◽

Co2 Hydrogenation ◽

Level Of Detail ◽

Reaction Pathways ◽

Catalytic Systems ◽

Computational Code ◽

Catalytic Cycles

<div><div><div><p>The computational study of catalytic processes allows discovering really intricate and detailed reaction mechanisms that involve many species and transformations. This increasing level of detail can even result detrimental when drawing conclusions from the computed mechanism, as many co-existing reaction pathways can be in close com- petence. Here we present a reaction network-based implementation of the energy span model in the form of a computational code, gTOFfee, capable of dealing with any user-specified reaction network. This approach, compared to microkinetic simulations, enables a much easier and straightforward analysis of the performance of any catalytic reaction network. In this communication, we will go through the foundations and appli- cability of the underlying model, and will tackle the application to two relevant catalytic systems: homogeneous Co-mediated propene hydroformylation and heterogeneous CO2 hydrogenation over Cu(111).</p></div></div></div>

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Prion Protein Aggregation Induced by Copper(II) and Heparan Sulfate. Pressure-dependent Switch of Reaction Pathways

Zeitschrift für Naturforschung B ◽

10.1515/znb-2008-0624 ◽

2008 ◽

Vol 63 (6) ◽

pp. 747-755 ◽

Cited By ~ 1

Author(s):

Driss El Moustaine ◽

Joan Torrent ◽

Reinhard Lange

Keyword(s):

Heparan Sulfate ◽

Prion Protein ◽

Conformational Changes ◽

Atmospheric Pressure ◽

Amyloid Fibrils ◽

Copper Ions ◽

Fibril Formation ◽

Cellular Prion Protein ◽

Reaction Pathways ◽

Structural Alterations

Copper ions (Cu2+) and heparan sulfate (HS) are suspected to act as regulatory agents in the conversion of cellular prion protein (PrPC) to its infectious isoform. However, the mechanism of this reaction is still largely unknown. Our previous report suggested multidimensional pathways for structural alterations of PrP, which may be modulated by high pressure (HP). Here we use HP to investigate the effects of Cu2+ and HS binding on PrP conformational changes and assembly. In the presence of Cu2+, amyloid fibrils are formed only under HP. In contrast, in the presence of HS, fibrils are formed at atmospheric pressure, but not under HP. Both compounds appear to compete for the same binding site, since HS-supported fibril formation is quenched by Cu2+. Inversely, Cu2+- mediated fibril formation under HP is inhibited by HS.

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CO2-Enabled Cyanohydrin Synthesis and Facile Homologation Reactions

10.26434/chemrxiv.12652361.v1 ◽

2020 ◽

Author(s):

Martin Juhl ◽

Allan Petersen ◽

JIWOONG LEE

Keyword(s):

Atmospheric Pressure ◽

Chemical Process ◽

Reaction Rates ◽

Protecting Groups ◽

Reaction Pathways ◽

Easy Access ◽

Kinetic Control ◽

Direct Reaction ◽

Fischer Synthesis ◽

Cyanohydrin Synthesis

Thermodynamic and kinetic control of a chemical process is the key to access desired products and states. Changes are made when desired product is not accessible; one may manipulate the reaction with additional reagents, catalysts and/or protecting groups. Here we report the use of carbon dioxide to direct reaction pathways in order to selectively afford desired products in high reaction rates while avoiding the formation of byproducts. The utility of CO<sub>2</sub>-mediated selective cyanohydrin synthesis was further showcased by broadening Kiliani-Fischer synthesis to offer an easy access to variety of polyols, cyanohydrins, linear alkylnitriles, by simply starting from alkyl- and arylaldehydes, KCN and atmospheric pressure of CO<sub>2</sub>.

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Enhanced methanol production by two-stage reaction of CO2 hydrogenation at atmospheric pressure

Catalysis Communications ◽

10.1016/j.catcom.2021.106373 ◽

2021 ◽

pp. 106373

Author(s):

Ya-Ning Yang ◽

Chao-Wei Huang ◽

Van-Huy Nguyen ◽

Jeffrey C.-S. Wu

Keyword(s):

Atmospheric Pressure ◽

Co2 Hydrogenation ◽

Two Stage ◽

Methanol Production

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Tuning Adsorption Energies and Reaction Pathways by Alloying: PdZn versus Pd for CO2 Hydrogenation to Methanol

The Journal of Physical Chemistry Letters ◽

10.1021/acs.jpclett.0c02011 ◽

2020 ◽

Vol 11 (18) ◽

pp. 7672-7678

Author(s):

Florian Brix ◽

Valentin Desbuis ◽

Laurent Piccolo ◽

Émilie Gaudry

Keyword(s):

Co2 Hydrogenation ◽

Reaction Pathways ◽

Adsorption Energies

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CO2 Hydrogenation at Atmospheric Pressure and Low Temperature Using Plasma-Enhanced Catalysis over Supported Cobalt Oxide Catalysts

ACS Sustainable Chemistry & Engineering ◽

10.1021/acssuschemeng.0c05565 ◽

2020 ◽

Vol 8 (47) ◽

pp. 17397-17407 ◽

Cited By ~ 2

Author(s):

Maria Ronda-Lloret ◽

Yaolin Wang ◽

Paula Oulego ◽

Gadi Rothenberg ◽

Xin Tu ◽

...

Keyword(s):

Low Temperature ◽

Cobalt Oxide ◽

Atmospheric Pressure ◽

Co2 Hydrogenation ◽

Oxide Catalysts

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Intermetallic PdIn catalyst for CO2 hydrogenation to methanol: mechanistic studies with a combined DFT and microkinetic modeling method

Catalysis Science & Technology ◽

10.1039/c9cy01242g ◽

2019 ◽

Vol 9 (21) ◽

pp. 6102-6113 ◽

Cited By ~ 15

Author(s):

Panpan Wu ◽

Bo Yang

Keyword(s):

Density Functional Theory ◽

Carbon Monoxide ◽

Density Functional ◽

Co2 Hydrogenation ◽

Modeling Method ◽

Reaction Pathways ◽

Mechanistic Studies ◽

Microkinetic Modeling ◽

Functional Theory ◽

Carbon Monoxide Formation

Reaction pathways of methanol and carbon monoxide formation from CO2 hydrogenation over PdIn(110) and (211) with a combined density functional theory and microkinetic modeling approach.

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