The combustion of aromatic and alicyclic hydrocarbons. IV. The kinetics of the slow combustion of benzene and its mono-alkyl derivatives at low temperatures

In previous papers of this series the ignition and slow-combustion reactions of a number of aromatic hydrocarbons have been examined, mainly from the kinetic standpoint. In the present and following communications it is proposed further to consider benzene and its single side-chain derivatives, in relation particularly to the oxidation reactions occurring below 400° C, and to correlate this mode of combustion by kinetic and analytical observations with the types previously examined. The hydrocarbons to which attention is chiefly directed are benzene, toluene, ethylbenzene, n -propylbenzene and n -butylbenzene.

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The combustion of aromatic and alicyclic hydrocarbons. II. The ignition of aromatic hydrocarbons at high temperatures

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1939.0075 ◽

1939 ◽

Vol 171 (946) ◽

pp. 421-433 ◽

Cited By ~ 2

Keyword(s):

High Temperatures ◽

Aromatic Hydrocarbons ◽

Isothermal Oxidation ◽

Present Communication ◽

Temperature Range ◽

Benzene Toluene ◽

The Subject ◽

Kinetics Of

In the first paper of this series (Burgoyne 1937) the kinetics of the isothermal oxidation above 400° C of several aromatic hydrocarbons was studied. The present communication extends this work to include the phenomena of ignition in the same temperature range, whilst the corresponding reactions below 400° C form the subject of further investigations now in progress. The hydrocarbons at present under consideration are benzene, toluene, ethylbenzene, n -propylbenzene, o-, m - and p -xylenes and mesitylene.

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The oxidation of aromatic hydrocarbons at high pressures. I— Benzene. II— Toluene. III— Ethyl Benzene

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1936.0014 ◽

1936 ◽

Vol 153 (879) ◽

pp. 448-462 ◽

Cited By ~ 13

Keyword(s):

Aromatic Hydrocarbons ◽

High Pressures ◽

Vapour Phase ◽

Complete Analysis ◽

Ethyl Benzene ◽

Open Chain ◽

Slow Combustion ◽

Benzene Toluene ◽

A Chain ◽

Oxidation Of Benzene

It has been shown in previous papers of this series that during the slow combustion of the aliphatic hydrocarbons at high pressure conditions are particularly favourable to the isolation of the intermediate compounds involved, and that such oxidations take place by successive stages of hydroxylation. The work has now been extended to include the aromatic hydrocarbons, and the present paper embodies the results for benzene, toluene, and ethyl benzene. The homogeneous slow oxidation of benzene in the vapour phase has been studied by Fort and Hinshelwood, who concluded that at atmospheric pressure it proceeds by a chain mechanism somewhat analogous to that which they postulated for ethylene. Although a complete analysis of the products of combustion was not made, other circumstances suggested that during an "apparent period of induction" the first products were formed without pressure increase, and that, to quote their words, 'hydroxylation of the double bonds may be assumed to occur, followed by rapid further oxidation of the open chain unsaturated compound so produced to a substance like glyoxal. The remaining stages would then be analagous to the oxidation of acetylene

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The combustion of aromatic and alicyclic hydrocarbons I—The slow combustion of benzene, toluene, ethylbenzene, n -propylbenzene, n -butylbenzene, o -xylene, m -xylene, p -xylene and mesitylene

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1937.0131 ◽

1937 ◽

Vol 161 (904) ◽

pp. 48-67 ◽

Cited By ~ 9

Keyword(s):

Gaseous Phase ◽

Aromatic Compounds ◽

Chain Mechanism ◽

Induction Periods ◽

Slow Combustion ◽

Benzene Toluene ◽

Chain Theory ◽

Characteristic Features ◽

A Chain ◽

Kinetics Of

Recent work upon the kinetics of the oxidation of aliphatic hydrocarbons has led to the recognition of certain characteristic features that find a ready interpretation in terms of the chain theory of chemical reaction. Thus, for example, both paraffins and olefines exhibit well-defined induction periods, pressure limits of inflammability and a marked sensitivity to the influence of surface, that point directly to the intervention of reaction chains; and although the precise nature of the chain mechanisms is somewhat uncertain a great deal of information is available as to their length, branching characteristics, mutual interactions and stability. Corresponding data for alicyclic and aromatic compounds are, however, very scanty and only in one instance has a comprehensive systematic kinetic study been made. Fort and Hinshelwood (1930) and Amiel (1933 a, b , 1936) have investigated the slow combustion of benzene and find that whilst it shows a general resemblance to ethylene there are certain respects in which significant differences occur. Fort and Hinshelwood concluded that benzene is oxidized by a chain mechanism, the chains initiated predominantly in the gaseous phase being of short continuation.

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Performance of Ag-HZSM-5 Zeolite Catalysts in n-heptane Conversion

Revista de Chimie ◽

10.37358/rc.17.1.5401 ◽

2017 ◽

Vol 68 (1) ◽

pp. 116-120

Author(s):

Iuliean Vasile Asaftei ◽

Neculai Catalin Lungu ◽

Lucian Mihail Birsa ◽

Ioan Gabriel Sandu ◽

Laura Gabriela Sarbu ◽

...

Keyword(s):

Aromatic Hydrocarbons ◽

Metal Content ◽

Pulse Method ◽

Acid Strength ◽

Strength Distribution ◽

Zeolite Catalysts ◽

Benzene Toluene ◽

Acid Strength Distribution ◽

Silver Cations ◽

Heptane Conversion

The conversion of n-heptanes into aromatic hydrocarbons benzene, toluene and xylenes (BTX), by the chromatographic pulse method in the temperature range of 673 - 823K was performed over the HZSM-5 and Ag-HZSM-5 zeolites modified by ion exchange with AgNO3 aqueous solutions. The catalysts, HZSM-5 (SiO2/Al2O3 = 33.9), and Ag-HZSM-5 (Ag1-HZSM-5 wt. % Ag1.02, Ag2-HZSM-5 wt. % Ag 1.62; and Ag3-HZSM-5 wt. % Ag 2.05 having different acid strength distribution exhibit a conversion and a yield of aromatics depending on temperature and metal content. The yield of aromatic hydrocarbons BTX appreciably increased by incorporating silver cations Ag+ into HZSM-5.

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Switching Cytolytic Nanopores into Antimicrobial Fractal Ruptures by a Single Side Chain Mutation

ACS Nano ◽

10.1021/acsnano.1c00218 ◽

2021 ◽

Author(s):

Katharine Hammond ◽

Flaviu Cipcigan ◽

Kareem Al Nahas ◽

Valeria Losasso ◽

Helen Lewis ◽

...

Keyword(s):

Side Chain ◽

Single Side

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Solid-State Redox Kinetics of CeO2 in Two-Step Solar CH4 Partial Oxidation and Thermochemical CO2 Conversion

Catalysts ◽

10.3390/catal11060723 ◽

2021 ◽

Vol 11 (6) ◽

pp. 723

Author(s):

Mahesh Muraleedharan Nair ◽

Stéphane Abanades

Keyword(s):

Solid State ◽

Solar Energy ◽

Kinetic Models ◽

Oxygen Carrier ◽

Co2 Conversion ◽

Oxidation Reactions ◽

Redox Kinetics ◽

Concentrated Solar Energy ◽

Ceria Reduction ◽

Kinetics Of

The CeO2/CeO2−δ redox system occupies a unique position as an oxygen carrier in chemical looping processes for producing solar fuels, using concentrated solar energy. The two-step thermochemical ceria-based cycle for the production of synthesis gas from methane and solar energy, followed by CO2 splitting, was considered in this work. This topic concerns one of the emerging and most promising processes for the recycling and valorization of anthropogenic greenhouse gas emissions. The development of redox-active catalysts with enhanced efficiency for solar thermochemical fuel production and CO2 conversion is a highly demanding and challenging topic. The determination of redox reaction kinetics is crucial for process design and optimization. In this study, the solid-state redox kinetics of CeO2 in the two-step process with CH4 as the reducing agent and CO2 as the oxidizing agent was investigated in an original prototype solar thermogravimetric reactor equipped with a parabolic dish solar concentrator. In particular, the ceria reduction and re-oxidation reactions were carried out under isothermal conditions. Several solid-state kinetic models based on reaction order, nucleation, shrinking core, and diffusion were utilized for deducing the reaction mechanisms. It was observed that both ceria reduction with CH4 and re-oxidation with CO2 were best represented by a 2D nucleation and nuclei growth model under the applied conditions. The kinetic models exhibiting the best agreement with the experimental reaction data were used to estimate the kinetic parameters. The values of apparent activation energies (~80 kJ·mol−1 for reduction and ~10 kJ·mol−1 for re-oxidation) and pre-exponential factors (~2–9 s−1 for reduction and ~123–253 s−1 for re-oxidation) were obtained from the Arrhenius plots.

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Gas phase interaction with catalytic oxidation reactions

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1972.0006 ◽

1972 ◽

Vol 326 (1565) ◽

pp. 215-227 ◽

Cited By ~ 7

Keyword(s):

Carbon Dioxide ◽

Maleic Anhydride ◽

Catalytic Oxidation ◽

Gas Phase ◽

Major Part ◽

Oxidation Reactions ◽

Mixed Gas ◽

Kinetics Of ◽

Oxidation Of Benzene ◽

Homogeneous Decomposition

Studies of the catalytic oxidation of benzene to maleic anhydride and carbon dioxide over vanadia/molybdena catalysts show that the major part of the reaction involves interacting gas and gas-solid processes. The results are consistent with a mechanism in which a benzeneoxygen adduct is formed catalytically, desorbs and then reacts to give maleic anhydride entirely in the gas phase. On the basis of this proposed mechanism, the kinetics of individual reactions have been investigated in some depth. The over-oxidation of maleic anhydride has been found to be not significant under the conditions of reaction. The kinetic relationships governing the homogeneous decomposition of the adduct and the oxidation of the adduct to maleic anhydride and to carbon dioxide have been established. The results show that essentially all of the anhydride originates from mixed gas-solid/gas reaction while substantial amounts of carbon dioxide are produced entirely catalytically.

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E-Homolupane Derivatives Substituted in Position 17 and 22a. 1H NMR, 13C NMR and IR Spectra

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950619 ◽

1995 ◽

Vol 60 (4) ◽

pp. 619-635 ◽

Cited By ~ 1

Author(s):

Václav Křeček ◽

Stanislav Hilgard ◽

Miloš Buděšínský ◽

Alois Vystrčil

Keyword(s):

Nmr Spectra ◽

2D Nmr ◽

Coupling Constants ◽

Side Chain ◽

Oxidation Reactions ◽

H Nmr ◽

Complete Assignment ◽

Nmr Techniques ◽

Intramolecular Association ◽

C Nmr

A series of derivatives with various oxygen functionalities in positions 17,22a or 19,20 was prepared from diene I and olefin XVI by addition and oxidation reactions. The structure of the obtained compounds was confirmed by 1H NMR, 13C NMR and IR spectroscopy. The kind of intramolecular association of the 17α-hydroxy group was studied in connection with modification of the side chain and substitution in position 22a. Complete assignment of the hydrogen signals and most of the coupling constants was accomplished using a combination of 1D and 2D NMR techniques. The 1H and 13C NMR spectra are discussed.

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Oxidation of Olefins Representing Some Structural Units of GR-S

Rubber Chemistry and Technology ◽

10.5254/1.3543370 ◽

1952 ◽

Vol 25 (1) ◽

pp. 21-32 ◽

Cited By ~ 1

Author(s):

W. C. Warner ◽

J. Reid Shelton

Keyword(s):

Phenyl Group ◽

Kinetic Mechanism ◽

Oxidation Reactions ◽

Chain Reaction ◽

Instantaneous Rate ◽

Initial Oxygen ◽

Oxidation Of Olefins ◽

A Minor ◽

The Relationship ◽

Kinetics Of

Abstract Three olefins were oxidized in the liquid phase with molecular oxygen to determine the kinetics of the oxidation reactions and the relationship to oxidation of rubber. The instantaneous rate of oxidation was found to be related to the analytically determined olefin and peroxide concentrations by the equation : Rate=k (unreacted olefin)(peroxide), where rate equals moles of oxygen per mole of original olefin per hour and the parentheses represent molarities. Presence of a phenyl group was found to affect k, but only in a minor way, indicating that the same fundamental kinetic mechanism applies in both aromatic and aliphatic olefins. The data are consistent with the general kinetic mechanism of Bolland involving oxygen attack at the alpha-methylenic group. However, it appears probable that initial oxygen attack can also occur at the double bond, resulting in the formation of a peroxide biradical, which may then react with other olefin molecules, initiating the usual chain reaction mechanism.

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