- Author
-
Bannister, W. W.
|
Donatelli, A.
|
Bonner, F.
|
Lai, F.
|
Kurup, P.
|
Egan, J.
|
Jahngen, E. G. E.
|
Muanchareon, P.
|
Paramasawat, W.
|
Sriseubsai, W.
|
Chiang, S. K.
|
Kongkadee, V.
|
Sengupta, S.
|
Nagarajan, R.
|
Euaphantasate, N.
|
Parma, V.
|
Cazeca, M.
|
Chen, E.
|
Morales, A.
- Title
- Anionic Effects in Hot Surface Combustions.
- Coporate
- Massachusetts Univ., Lowell
- Sponsor
- National Institute of Standards and Technology, Gaithersburg, MD
- Report
-
Paper 22; HOTWC 2005,
- Book or Conf
- Halon Options Technical Working Conference, 15th Proceedings. HOTWC 2005. Sponsored by: 3M Specialty Materials, Boeing, Chemical Development Studies, Inc., DuPont Fire Extinguishants, Halon Alternative Research Corp., Hughes Associates, Inc., Kidde-Fenwal, Inc., Sandia National Laboratories, SEVO Systems, Next Generation Fire Suppression Technology Program. May 24-26, 2005,
Albuquerque, NM,
1-13 p.,
2005
- Keywords
-
halon alternatives
|
halons
|
halon 1301
|
combustion
|
hot surfaces
|
equations
|
oxidation
|
ignition
|
hydrocarbons
|
electrostatic charges
- Identifiers
- oxidation of 9% CH4/air at 1050°C (about 500°C below maximum IT); seebeck effects favoring polar combustion mechanisms; thermoelectric power and ignition proclivity for combustion catalysts; oxyanionic and corroded surface effects; electrostatic field effects arising from surface microdefects; electrostatic force microscopy (EFM)
- Abstract
- Hot surface oxidations are commonly thought to involve initial free radical hydrogen atom abstraction. Our evidence implicates initial Lewis base deprotonation by O atomic oxygen radical anions to form negatively charged carbanions. Subsequent rate determining electron transfers generate free radicals which only then give rise to combustion. Correlations regarding ignition temperatures and hydrocarbon oxidation product identity are consistent with carbanionic but not free radical effects. Highly polarized surfaces (e.g., quartz and corroded surfaces), and addition of polar compounds to fuel/air mixtures facilitate ignitions. EFM confirms increased electrostatic intensities at microscopic surface defects. For seemingly uniformly hot surfaces there are transient widely disparate high temperature incandescent "red spot" zones due to flameless oxidations induced by concentrated electrostatic negative charges at surface defects. Isotope, ignition temperatures and combustion trends are consistent with Seebeck effects (ease of electron migration in unevenly heated areas). There are preliminary though not yet verified indications that electrostatic charges on hot surfaces may facilitate combustion. Implications would then involve fire mitigation and enhancement, and industrial manufacture of many important organic combustion products.