Comparison of the Ionic Mechanism of Soot Formation with a Free Radical Mechanism

  • Haetwell F. Calcote
  • Robert J. Gill
Part of the Springer Series in Chemical Physics book series (CHEMICAL, volume 59)

Abstract

The possible mechanisms by which large hydrocarbon ions might be produced in a fuel rich sooty flame are examined and all of them are eliminated except growth through ion-molecule reactions starting from the chemiion, HCO+. Large ions are not, as sometimes assumed, an indicator of neutral species. The ionic mechanism of soot nucleation is compared with a free radical mechanism by comparing the time each mechanism requires to add 10 carbon atoms to the growing species, ion or neutral. Experimental concentrations are combined with appropriate rate coefficients for the individual steps. The ionic mechanism appears to require less time, but the differences are within the accuracy of the data available.

Keywords

Combustion Benzene Recombination Hydrocarbon Phenyl 

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References

  1. 29.1
    H.F. Calcote, D.B. Olson, D.G. Keil: Energy Fuels 2, 494 (1988)CrossRefGoogle Scholar
  2. 29.2
    H.F. Calcote, D.G. Keil: Pure Appl. Chem. 62, 815 (1990)CrossRefGoogle Scholar
  3. 29.3
    H.F. Calcote, D.G. Keil: Combust. Flame 74, 131 (1988)CrossRefGoogle Scholar
  4. 29.4
    P. Gerhardt, K.H. Homann: Combust. Flame 81, 289 (1990)CrossRefGoogle Scholar
  5. 29.5
    J.L. Delfau, P. Michaud, A. Barassin: Combust. Sei. Technol. 20 165 (1979)CrossRefGoogle Scholar
  6. 29.6
    D.B. Olson, H.F. Calcote: “Ions in fuel-rich and sooting acetylene and benzene flames” in Eighteenth Symposium (International) on Combustion ( The Combustion Institute, Pittsburgh 1981 ) p. 453Google Scholar
  7. 29.7
    F.T. Smith: J. Chem. Phys. 34, 793 (1961)CrossRefGoogle Scholar
  8. 29.8
    H.F. Calcote: Combust. Flame 42, 215 (1981)CrossRefGoogle Scholar
  9. 29.9
    S.E. Stein, S.A. Kafafi: “Thermochemistry of Soot Formation”, in Proceeding on Fall Technical Meeting, Eastern Section (The Combustion Institute, NBS 1987 )Google Scholar
  10. 29.10
    A.N. Eraslan, R.C. Brown: Combust. Flame 74, 191 (1988)CrossRefGoogle Scholar
  11. 29.11
    K.H. Homann: “Precursor Formation” in “Soot Formation in Combustion” -an International Round Table Diskussion, ed. by H. Jander, H.Gg. Wagner ( Vandenhoeck and Ruprecht, Göttingen 1990 ) p. 127Google Scholar
  12. 29.12
    S.E. Stein: Combust. Flame 51 357 (1983)CrossRefGoogle Scholar
  13. 29.13
    P. Michaud, J.L. Delfau, A. Barassin: “The positive ion chemistry in the post-combustion zone of sooting premixed acetylene low pressure flat flames” in Eighteenth Symposium (International) on Combustion ( The Combustion Institute, Pittsburgh 1981 ) p. 443Google Scholar
  14. 29.14
    H.F. Calcote, R.J. Gill: in preparationGoogle Scholar
  15. 29.15
    H.F. Calcote: in Ion-Molecule Reactions, Vol. 2, ed. by J.L. Franklin ( Plenum Press, New York 1972 ) p. 673Google Scholar
  16. 29.16
    H.F. Calcote, R.J. Gill: “Computer Modeling of Soot Formation Comparing Free Radical and Ionic Mechanisms” AeroChem TP-495 (April 1991)Google Scholar
  17. 29.17
    M. Frenklach, J. Warnatz: Combust. Sei. Technol. 51, 265 (1987)CrossRefGoogle Scholar
  18. 29.18
    C. Vovelle, personal communication (December 1989)Google Scholar
  19. 29.19
    J.D. Bittner, J.B. Howard: “Preparticle chemistry in soot formation” in Particulate Carbon: Formation During Combustion, ed. by D.G. Siegla, G.W. Smith (Plenum Press, New York 1981 ) p. 109Google Scholar
  20. 29.20
    M. Frenklach, H. Wang: “Detailed modeling of soot particle nucleation and growth” in Twenty-Third Symposium (International) on Combustion ( The Combustion Institute, Pittsburgh 1991 ) p. 1559Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1994

Authors and Affiliations

  • Haetwell F. Calcote
    • 1
  • Robert J. Gill
    • 1
  1. 1.AeroChem Research Laboratories, Inc.PrincetonUSA

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