Reactions of C3H3Cl with H2, C3H4, C2H2 and C2H4 Behind Reflected Shock Waves

  • R. D. Kern
  • H. Chen
  • Z. Qin
  • K. Xie
Conference paper

Abstract

Mixtures of propargyl chloride diluted in neon have been studied by dynamic sampling of the reflected shock zone by time-of-flight mass spectrometry. For the C3H3Cl system, benzene is detected only in trace amounts as an expected product of reactions involving C3H3 radicals; only C2H2, C4H2 and HCl appear as major products. However, in mixtures of C3H3Cl containing H2, benzene is readily observed. Experiments on a 3% C3H3Cl - 5% D2 mixture reveal a constant temporal HCl/DCl product ratio that is approximately equal to 5. It is proposed that the major channel for C3H3Cl dissociation yields HCl and c-C3H2 (singlet cyclopropenylidene). In the presence of H2, c-C3H2 reacts exothermically to form the thermally excited adduct C3H4* which readily isomerizes to either allene or propyne as predicted by a bimolecular-QRRK calculation. The calculations reveal that formation of allene and propyne account for 89% of the product distribution in the reaction of c-C3H2 with H2. Benzene production is also recorded in mixtures of C3H3Cl + allene, C3H3CI + propyne, C3H3Cl + C2H2 and C3H3CI + C2H4. The products observed in these mixtures over the range 1350 - 1700 K are C2H2, C4H2, HCl, benzene and trace amounts of C6H2. The model utilizes a 36 step mechanism and yields satisfactory agreement between the calculated and experimental results.

Key words

Chemical reaction Benzene formation Time-of-flight mass spectrometry 

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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • R. D. Kern
    • 1
  • H. Chen
    • 1
  • Z. Qin
    • 1
  • K. Xie
    • 1
  1. 1.Department of ChemistryUniversity of New OrleansNew OrleansUSA

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