The persistent radical effect: a prototype example of extreme, 105 to 1, product selectivity in a free-radical reaction involving persistent .cntdot.CoII[macrocycle] and alkyl free radicals

1992 ◽  
Vol 114 (8) ◽  
pp. 2938-2943 ◽  
Author(s):  
Brian E. Daikh ◽  
Richard G. Finke
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Radical Reaction ◽  
Free Radical Reaction ◽  
Product Selectivity

Study on Reaction Mechanism during the Pyrolysis of Coal to Acetylene in the Plasma

2013 ◽  
Vol 634-638 ◽  
pp. 1637-1642 ◽  
Author(s):  
Yuan Yu Tian ◽  
Ying Yun Qiao ◽  
Ke Chang Xie
Keyword(s):  
Free Radicals ◽  
High Temperature ◽  
Free Radical ◽  
Reaction Mechanism ◽  
Radical Reaction ◽  
Free Radical Reaction ◽  
Temperature Plasma ◽  
Organic Product ◽  
Plasma Reaction ◽  
Chemical Groups

The pyrolysis of coal to acetylene is studied with Pingshuo coal, Zichang coal and Dongshan coal in the plasma, and its course is analysised by coal chemical groups. The reaction mechanism of imitate free radicals is proposed in the pyrolysis of coal to acetylene in the plasma, the free radicals formation of high-temperature plasma and the composite dynamics are discussed. The results can educe that the acetylene content is higher of the organic product in the high temperature center zone of the pyrolysis of coal to acetylene in the plasma which base on the discussion of the saturates free radicals generating and compounding, combine with the reaction of aromatics, colloids and asphaltene and carbenes. It also can indicate that free radical reaction mechanism is applicable and feasible to explain coal of high-temperature centre zone in the plasma reaction.

scholarly journals A Study of the Mechanisms of Guaiacol Pyrolysis Based on Free Radicals Detection Technology

Catalysts ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 295 ◽  
Author(s):  
Guoxiang Li ◽  
Zhongyang Luo ◽  
Wenbo Wang ◽  
Jianmeng Cen
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Radical Reaction ◽  
Free Radical Reaction ◽  
Methyl Radicals ◽  
Paramagnetic Resonance ◽  
Lignin Model Compound ◽  
Detection Technology ◽  
Lignin Model ◽  
Hydrogen Radicals

In order to understand the reaction mechanism of lignin pyrolysis, the pyrolysis process of guaiacol (o-methoxyphenol) as a lignin model compound was studied by free radical detection technology (electron paramagnetic resonance, EPR) in this paper. It was proven that the pyrolysis reaction of guaiacol is a free radical reaction, and the free radicals which can be detected mainly by EPR are methyl radicals. This paper proposes a process in which four free radicals (radicals 1- C6H4(OH)O*, radicals 5- C6H4(OCH3)O*, methyl radicals, and hydrogen radicals) are continuously rearranged during the pyrolysis of guaiacol.

Kinetics of the Production of Castor Oil Maleate through the Autocatalyzed Thermal Reaction and the Free Radical Reaction

2017 ◽  
Vol 50 (2) ◽  
pp. 112-121 ◽  
Author(s):  
Dayanne L. H. Maia ◽  
Elenilson G. Alves Filho ◽  
Antonino F. Barros Junior ◽  
Fabiano A. N. Fernandes
Keyword(s):  
Free Radical ◽  
Castor Oil ◽  
Radical Reaction ◽  
Thermal Reaction ◽  
Free Radical Reaction ◽  
Kinetics Of

Manganese(III)-based oxidative free-radical reaction of α-allyl-β-keto ester with molecular oxygen

1993 ◽  
Vol 34 (52) ◽  
pp. 8509-8512 ◽  
Author(s):  
Takashi Ohshima ◽  
Mikiko Sodeoka ◽  
Masakatsu Shibasaki
Keyword(s):  
Free Radical ◽  
Molecular Oxygen ◽  
Radical Reaction ◽  
Free Radical Reaction ◽  
Keto Ester

scholarly journals Gasification Pathways and Reaction Mechanisms of Primary Alcohols in Supercritical Water

2019 ◽  
Author(s):  
Brian Pinkard ◽  
John Kramlich ◽  
Igor V. Novosselov
Keyword(s):  
Free Radical ◽  
Supercritical Water ◽  
Reaction Mechanisms ◽  
Radical Reaction ◽  
Water Environment ◽  
Waste To Energy ◽  
Reaction Pathways ◽  
Free Radical Reaction ◽  
Reaction Products ◽  
Primary Alcohols

<div> <p></p><p>Supercritical water gasification is a promising waste-to-energy technology with the ability to convert aqueous and/or heterogeneous organic feedstocks to high-value gaseous products. Reaction behavior of complex molecules in supercritical water can be inferred through knowledge of the reaction pathways of model compounds in supercritical water. In this study methanol, ethanol, and isopropyl alcohol are gasified in a continuous supercritical water reactor at temperatures between 500 and 560 °C, and for residence times between 3 and 8 s. <i>In situ</i> Raman spectroscopy is used to rapidly identify and quantify reaction products. The results suggest the dominance of chain-branching, free radical reaction mechanisms that are responsible for decomposing primary alcohols in the supercritical water environment. The presence of a catalytic surface is proposed to be highly significant for initiating radical reactions. Global reaction pathways are proposed, and mechanisms for free radical reaction initiation, propagation, and termination are discussed in light of these and previously published experimental results.</p><br><p></p></div>

scholarly journals Gasification Pathways and Reaction Mechanisms of Primary Alcohols in Supercritical Water

2019 ◽  
Author(s):  
Brian Pinkard ◽  
John Kramlich ◽  
Igor V. Novosselov
Keyword(s):  
Free Radical ◽  
Supercritical Water ◽  
Reaction Mechanisms ◽  
Radical Reaction ◽  
Water Environment ◽  
Waste To Energy ◽  
Reaction Pathways ◽  
Free Radical Reaction ◽  
Reaction Products ◽  
Primary Alcohols

<div> <p></p><p>Supercritical water gasification is a promising waste-to-energy technology with the ability to convert aqueous and/or heterogeneous organic feedstocks to high-value gaseous products. Reaction behavior of complex molecules in supercritical water can be inferred through knowledge of the reaction pathways of model compounds in supercritical water. In this study methanol, ethanol, and isopropyl alcohol are gasified in a continuous supercritical water reactor at temperatures between 500 and 560 °C, and for residence times between 3 and 8 s. <i>In situ</i> Raman spectroscopy is used to rapidly identify and quantify reaction products. The results suggest the dominance of chain-branching, free radical reaction mechanisms that are responsible for decomposing primary alcohols in the supercritical water environment. The presence of a catalytic surface is proposed to be highly significant for initiating radical reactions. Global reaction pathways are proposed, and mechanisms for free radical reaction initiation, propagation, and termination are discussed in light of these and previously published experimental results.</p><br><p></p></div>

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