Formation of Trace Byproducts in the Premixed Flames of CH3Cl/C2H4

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• 作者：Jiawei Huang ; Isik Onal ; and Selim M. Senkan
• 刊名：Environmental Science & Technology
• 出版年：1997
• 出版时间：May 1997
• 年：1997
• 卷：31
• 期：5
• 页码：1372 - 1381
• 全文大小：264K
• 年卷期：v.31,no.5(May 1997)
• ISSN：1520-5851

文摘

The chemical structure of an atmospheric pressure, fuel-rich (equivalence ratio 3.06), flat flame of achloromethaneand ethylene (CH₃Cl/C₂H₄ =1.99) has been studiedexperimentally using both heated microprobe and cold trapsampling techniques followed by high-resolution gas chromatography/mass spectrometry (GC/MS). The identitiesand absolute concentrations of more than 50 major andminorhydrocarbon and chlorinated hydrocarbon species havebeen established, including a large number of aromatics,substituted aromatics, and polycyclic aromatic hydrocarbons (PAHs). Although some chlorinated PAHs were alsodetected, unsubstituted aromatics dominated the PAHproduct distribution. Mole fractions determined were intherange of 0.45-2.0 × 10^-7, with theheaviest PAHs at mass226 (C₁₈H₁₀,benzo[ghi]fluoranthene andcyclopenta-[cd]pyrene). The measurements indicated theselectivesuppression of certain PAHs, e.g.,cyclopenta[cd]pyrene, inthe presence of HCl when compared to regular hydrocarbonflames. Heated silica surfaces of the sampling probeandtransfer lines were also noted to chlorinate select PAHs,such as pyrene and acenaphthylene. The mole fractionprofilesof many of the products first increased, then decreased,and increased again in the post-flame zone. A numberofoxygenated aromatics were also detected. Thesemeasurements provide new information on the identities andlevels of hazardous air pollutants formed in theincinerationof chlorinated hydrocarbons and represent useful data forthe development and validation of detailed reaction mechanisms.