Gas-phase reaction of CeVO5+ cluster ions with C2H4: the reactivity of cluster bonded peroxides

The reactivity of the peroxide unit with hydrocarbon molecules on transition metal oxide clusters with a closed-shell electronic structure has been identified for the first time.

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Hydrogenation of CO2 over 15% Fe/SiO2 Catalyst under Sub- and Supercritical Conditions

Kataliz v promyshlennosti ◽

10.18412/1816-0387-2018-4-57-63 ◽

2018 ◽

Vol 18 (4) ◽

pp. 57-63

Author(s):

N. D. Evdokimenko ◽

K. O. Kim ◽

G. I. Kapustin ◽

N. A. Davshan ◽

A. L. Kustov

Keyword(s):

Gas Phase ◽

Atmospheric Pressure ◽

Iron Nanoparticles ◽

Catalyst Surface ◽

Phase Reaction ◽

Supercritical Conditions ◽

Gas Phase Reaction ◽

Xrd Studies ◽

First Time ◽

Hydrogenation Of Co

The results of comparative studies of CO2hydrogenation over 15% Fe/SiO2catalyst under sub- and supercritical conditions are presented for the first time. The reaction was studied at 300–500 °C and atmospheric pressure in gas phase and at 95 atm under supercritical conditions. The molar H2: CO2ratio was 2 : 1. Under supercritical conditions, the selectivity to CO2decreased from 90–95 to 30–50 % at all temperatures, while the selectivity to hydrocarbons increased up to 60 %. The reaction under supercritical conditions, unlike gas-phase hydrogenation, produced alcohols. TG-DTG-DTA techniques were used to demonstrate 2.2-fold decrease in the quantity of carbon-like deposits in comparison to that in the gas-phase reaction. XRD studies revealed the formation of graphite-like species on the catalyst surface under gas-phase but not supercritical conditions. The developed process and catalyst for hydrogenation of CO2can be recommended to be further modified in order to improve the catalyst based on iron nanoparticles that is as expensive as 0.1–0.01 of the known catalysts for CO2hydrogenation.

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Degradation mechanism of 2-fluoropropene by Cl atoms: experimental and theoretical products distribution studies

Physical Chemistry Chemical Physics ◽

10.1039/d1cp03214c ◽

2021 ◽

Author(s):

Cynthia Rivela ◽

Alejandro L. Cardona ◽

Maria B Blanco ◽

Ian Barnes ◽

Martina Kieninger ◽

...

Keyword(s):

Gas Phase ◽

Quartz Glass ◽

Atmospheric Pressure ◽

Degradation Mechanism ◽

Phase Reaction ◽

Reaction Products ◽

Gas Phase Reaction ◽

Distribution Studies ◽

First Time ◽

Cl Atoms

The gas-phase reaction products of 2-fluoropropene (2FP) with Cl atoms has been determined for the first time at 298 K and atmospheric pressure using a 1080 L quartz-glass photoreactor coupled...

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Prediction of Alkanolamine pKa Values by Combined Molecular Dynamics Free Energy Simulations and ab initio Calculations

10.26434/chemrxiv.11215025 ◽

2019 ◽

Author(s):

Javad Noroozi ◽

William Smith

Keyword(s):

Molecular Dynamics ◽

Free Energy ◽

Ab Initio Calculations ◽

Gas Phase ◽

Quantum Chemical ◽

Phase Reaction ◽

Pka Values ◽

Gas Phase Reaction ◽

Reaction Free Energy ◽

Energy Simulations

We use molecular dynamics free energy simulations in conjunction with quantum chemical calculations of gas phase reaction free energy to predict alkanolamines pka values. <br>

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Redox Potential - (Electronic) Structure Relationships in 18- and 17-Electron Mononitrile (or Monocarbonyl) Diphosphine Complexes of Re and Fe

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20010139 ◽

2001 ◽

Vol 66 (1) ◽

pp. 139-154 ◽

Cited By ~ 11

Author(s):

M. Fátima C. Guedes Da Silva ◽

Luísa M. D. R. S. Martins ◽

João J. R. Fraústo Da Silva ◽

Armando J. L. Pombeiro

Keyword(s):

Cyclic Voltammetry ◽

Electronic Structure ◽

Binding Sites ◽

Closed Shell ◽

Carbonyl Complexes ◽

Metal Centre ◽

Pt Electrode ◽

Metal Site ◽

Oxidation Potentials ◽

First Time

The organonitrile or carbonyl complexes cis-[ReCl(RCN)(dppe)2] (1) (R = 4-Et2NC6H4 (1a), 4-MeOC6H4 (1b), 4-MeC6H4 (1c), C6H5 (1d), 4-FC6H4 (1e), 4-ClC6H4 (1f), 4-O2NC6H4 (1g), 4-ClC6H4CH2 (1h), t-Bu (1i); dppe = Ph2PCH2CH2PPh2), or cis-[ReCl(CO)(dppe)2] (2), as well as trans-[FeBr(RCN)(depe)2]BF4 (3) (R = 4-MeOC6H4 (3a), 4-MeC6H4 (3b), C6H5 (3c), 4-FC6H4 (3d), 4-O2NC6H4 (3e), Me (3f), Et (3g), 4-MeOC6H4CH2 (3h); depe = Et2PCH2CH2PEt2), novel trans-[FeBr(CO)(depe)2]BF4 (4) and trans-[FeBr2(depe)2] (5) undergo, as revealed by cyclic voltammetry at a Pt-electrode and in aprotic non-aqueous medium, two consecutive reversible or partly reversible one-electron oxidations assigned as ReI → ReII → ReIII or FeII → FeIII → FeIV. The corresponding values of the oxidation potentials IE1/2ox and IIE1/2ox (waves I and II, respectively) correlate with the Pickett's and Lever's electrochemical ligand and metal site parameters. This allows to estimate these parameters for the various nitrile ligands, depe and binding sites (for the first time for a FeIII/IV couple). The electrochemical ligand parameter show dependence on the "electron-richness" of the metal centre. The values of IE1/2ox for the ReI complexes provide some supporting for a curved overall relationship with the sum of Lever's electrochemical ligand parameter. The Pickett parametrization for closed-shell complexes is extended now also to 17-electron complexes, i.e. with the 15-electron ReII and FeIII centres in cis-{[ReCl(dppe)2]}+ and trans-{FeBr(depe)2}2+, respectively.

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