Dimerization of the Benzyl Radical in a High‐Temperature Pyrolysis Reactor Investigated by IR/UV Ion Dip Spectroscopy

We investigate the self‐reaction of benzyl, C7H7, in a high‐temperature pyrolysis reactor. The work is motivated by the observation that resonance‐stabilized benzyl radicals can accumulate in reactive environments and contribute to the formation of polycyclic aromatic hydrocarbons (PAHs) and soot. R...

Full description

Saved in:
Bibliographic Details
Published in:Chemistry : a European journal 2018-05, Vol.24 (30), p.7647-7652
Main Authors: Hirsch, Florian, Constantinidis, Philipp, Fischer, Ingo, Bakels, Sjors, Rijs, Anouk M.
Format: Article
Language:English
Subjects:
Chemistry
Dihydrophenanthrene
Dimerization
Fluorene
gas-phase reactions
high-temperature chemistry
Infrared radiation
Infrared spectroscopy
IR spectroscopy
Phenanthrene
Polycyclic aromatic hydrocarbons
Pyrolysis
radical reactions
Reaction products
Reactive environments
Reactors
Soot
Spectroscopy
Spectrum analysis
Stilbene
Toluene
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We investigate the self‐reaction of benzyl, C7H7, in a high‐temperature pyrolysis reactor. The work is motivated by the observation that resonance‐stabilized benzyl radicals can accumulate in reactive environments and contribute to the formation of polycyclic aromatic hydrocarbons (PAHs) and soot. Reaction products are detected by IR/UV ion dip spectroscopy, using infrared radiation from the free electron laser FELIX, and are identified by comparison with computed spectra. Among the reaction products identified by their IR absorption are several PAHs linked to toluene combustion such as bibenzyl, phenanthrene, diphenylmethane, and fluorene. The identification of 9,10‐dihydrophenanthrene provides evidence for a mechanism of phenanthrene formation from bibenzyl that proceeds by initial cyclization rather than an initial hydrogen loss to stilbene. Radical self‐reaction: The self‐reaction of benzyl radicals at high temperature, studied with IR/UV ion dip spectroscopy, leads to phenanthrene and fluorene as polycyclic aromatic hydrocarbons.
ISSN:0947-6539
1521-3765
DOI:10.1002/chem.201800852