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Платонов, В. В.; Proskuryakov, V. A.; Ryl'tsova, S. V.; Popova, Yu. N.

doi:10.1023/a:1013076330586

Cited by 10 publications

(8 citation statements)

References 3 publications

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“…A good prediction of experimental data was reached for anisole, carbon monoxide, methylcyclopentadiene, and total phenolic compounds. More recently, Platonov et al [21] showed the formation of various decomposition products, including PAHs, during the pyrolysis of anisole at high temperature (1023-1173 K). Friderichsen et al [22] used a hyperthermal nozzle and a flow tube reactor followed by analysis by mass spectrometry and FTIR spectroscopy.…”

Section: H 5 Och 3 C 6 H 5 O + Chmentioning

confidence: 99%

“…Naphthalene formation was attributed also to cyclopentadienyl radical combination. The most recent paper dealing with anisole [25] proposed a new kinetic mechanism validated against experimental data from Pecullan et al [20] and Platonov et al [21]. The literature review shows that anisole is a fragile compound, which reacts easily by unimolecular O-CH 3 bond breaking, which leads to methyl and phenoxy radicals.…”

Section: H 5 Och 3 C 6 H 5 O + Chmentioning

confidence: 99%

See 1 more Smart Citation

Detailed kinetic study of anisole pyrolysis and oxidation to understand tar formation during biomass combustion and gasification

Nowakowska

Herbinet

Dufour

et al. 2014

Combustion and Flame

129

157

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Section: H 5 Och 3 C 6 H 5 O + Chmentioning

confidence: 99%

Section: H 5 Och 3 C 6 H 5 O + Chmentioning

confidence: 99%

Detailed kinetic study of anisole pyrolysis and oxidation to understand tar formation during biomass combustion and gasification

Nowakowska

Herbinet

Dufour

et al. 2014

Combustion and Flame

129

157

View full text Add to dashboard Cite

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“…A number of comprehensive and fundamental theory-based mechanistic and kinetic studies have been performed for the pyrolysis of contracted lignin models, such as anisole, − o- quinone methide ( o- QM), ,, catechol, , hydroquinone, , chroman, , phenol, − and arylcumaran, which are believed to be the key intermediates in lignin thermolysis and char formation. ,, The H-abstraction of the phenolic hydroxyl groups, for instance, is believed to initiate formation of the ortho -quinone methide ( o- QM) intermediate involving a methoxy group, whereas the chroman formation is explained via ring closure processes. , The dimerization of p- coumaryl alcohol has been linked to the formation of a para -QM intermediate …”

Section: Introductionmentioning

confidence: 99%

Molecular Products and Fundamentally Based Reaction Pathways in the Gas-Phase Pyrolysis of the Lignin Model Compound p-Coumaryl Alcohol

et al. 2017

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The fractional pyrolysis of lignin model compound para-coumaryl alcohol (p-CMA) containing a propanoid side chain and a phenolic OH group was studied using the System for Thermal Diagnostic Studies at temperatures from 200 to 900 °C, in order to gain mechanistic insight into the role of large substituents in high-lignin feedstocks pyrolysis. Phenol and its simple derivatives p-cresol, ethyl-, propenyl-, and propyl-phenols were found to be the major products predominantly formed at low pyrolysis temperatures (<500 °C). A cryogenic trapping technique was employed combined with EPR spectroscopy to identify the open-shell intermediates registered at pyrolysis temperatures above 500 °C. These were characterized as radical mixtures primarily consisting of oxygen-linked conjugated radicals. A comprehensive potential energy surface analysis of p-CMA and p-CMA + H atom systems was performed using various DFT protocols to examine the possible role of concerted molecular eliminations and free-radical mechanisms in the formation of major products. Other significant unimolecular concerted reactions along with formation and decomposition of primary radicals are also described and evaluated. The calculations suggest that a set of the chemically activated secondary radical channels is relevant to the low temperature product formation under fractional pyrolysis conditions.

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“…A full set of these products were reported along with some other ring compounds in several papers. 1,7,9,11 The presence of phenol as one of the ring products, which is a clear indication of the retention of the CO bond between the phenyl carbon and the oxygen, was reported in all of the papers 1,612 except for an MS (mass spectroscopy) study of anisole pyrolysis. 5 This earliest work at a very high temperature of 950°C referred to the possibility of formation and decomposition of phenoxy to carbon monoxide.…”

Section: Resultsmentioning

confidence: 93%

“…1,69,12 Methane was found in most of the papers. 1,6,7,9,11,12 In several papers, 1,7,911 benzene was found as the ring product, always accompanied by phenol and carbon monoxide. All of the information on the product distribution implies the phenyl ring retention and is not contradictory to the bimolecular proton-transfer step (eq 2) followed by the unimolecular proton-transfer step (eq 1).…”

Section: Resultsmentioning

confidence: 99%

Pathways and Kinetics of Anisole Pyrolysis Studied by NMR and Selective 13C Labeling. Heterolytic Carbon Monoxide Generation

Tsujino¹,

Yasaka²,

Matubayasi³

et al. 2011

Bulletin of the Chemical Society of Japan

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It is important to investigate the kinetics and mechanisms of the thermal reaction process of ethers in order to understand more deeply high-temperature reactions and to develop more efficient high-temperature cracking and processing of fossil (oil and coal) and biomass fuels. In the previous letter, 1 we reported a kinetic study on the noncatalytic pyrolysis of the asymmetric ether, anisole (methyl phenyl ether), at 1 M and at 400430°C. By the product analysis with the gas-and liquid-phase NMR we have succeeded in revealing that the thermal fragmentation of the ether is induced by not homolytic (radical) but heterolytic (ionic) CH bond fission, and that the reaction consists of the slow and the fast elementary steps: (1) The slow step is the unimolecular CH bond fission that is initiated by the intramolecular proton transfer from the methyl to the phenyl group to generate the reactive intermediate formaldehyde (HCHO*). (2) The fast step is composed of the successive intermolecular proton and hydride transfers over the electronegative oxygen atom from the thermally excited intermediate HCHO*, respectively, to the phenoxy and methyl groups of the parent anisole molecule. They are expressed as:C 6 H 5 OCH 3 ! C 6 H 6 þ HCHO Ã ðslowÞ ð 1ÞAs represented here, the major products of the high-pressure (concentration) pyrolysis are benzene, phenol, methane, and carbon monoxide, all in almost equal amounts. The intramolecular proton transfer induced by the COC bending mode was also observed for acetaldehyde, 2 and dimethyl and diethyl ethers; This is called "hinge reaction" at high temperature. 3,4When the elementary steps assumed previously (see below) were the case, CO carbon should come from the methoxy but not from the phenoxy. To test this, here we have selectively labeled the asymmetric ether, anisole, by 13 C as C 6 H 5 O 13 CH 3 . In all of the earlier papers, 512 the following radical CO pathway was postulated:The homolytic bond breakage is assumed to take place between the ether oxygen (eq 3) and the methyl carbon to generate the methyl and phenoxy radicals, and furthermore, the ring-size reduction is presumed to give rise to CO as in eq 4. The thermal fragmentation of dimethyl ether, which is regarded as the prototype of the "unimolecular reaction," has been believed to have the radical mechanism since the pioneering work by Hinshelwood and co-workers in the 1920s. 13 The methoxy group is a key characteristic of these symmetric and asymmetric ethers, and the reactive intermediate formaldehyde* is expected to be generated for both cases. The asymmetric ether can be a promising candidate to distinguish the reaction pathways for the generated hydrocarbon fragments: benzene and methane for anisole and only methane twins for dimethyl ether. Convincing evidence is wanted to resolve the discrepancy in the mechanism of the fundamental thermal reaction. To this end we have scrutinized the CO generation pathway by applying highresolution NMR spectroscopy to the labeled anisole studied in the dark to carefully avoid the ...

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Cited by 10 publications

References 3 publications

Detailed kinetic study of anisole pyrolysis and oxidation to understand tar formation during biomass combustion and gasification

Detailed kinetic study of anisole pyrolysis and oxidation to understand tar formation during biomass combustion and gasification

Molecular Products and Fundamentally Based Reaction Pathways in the Gas-Phase Pyrolysis of the Lignin Model Compound p-Coumaryl Alcohol

Pathways and Kinetics of Anisole Pyrolysis Studied by NMR and Selective 13C Labeling. Heterolytic Carbon Monoxide Generation

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