Ionic Mechanisms of Soot Formation in Flames.
Abstract
The mass range of ions sampled from low pressure (2.7 kPa) acetylene-oxygen flames was extended to approximately 600 amu which made it necessary to calibrate the mass spectrometer mass scale. This was done by adding salts to the feed gases and by using deuterated acetylene as fuel. These experiments also allowed determination of the number of hydrogen atoms in a given ion, from which the structures of the flame ions up to mass 559 were deduced. Mass spectra were obtained for ten acetylene-oxygen flames with equivalence ratios of 1.0 to 3.0. The possibility that the large ions observed in sooting flames are derived from heating of small growing soot particles by exothermic surface reactions was examined theoretically. Although the necessary data for such a calculation are not accurately known, a temperature of soot particles about 100 K above the gas temperature was calculated. Equilibrium ionization of soot particles with this temperature enhancement could not account for the observed degree of ionization.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1986
- Accession Number
- ADA173631
Entities
People
- D. G. Keil
- H. F. Calcote