Accession Number:

ADA452714

Title:

Initiation in H2/O2: Rate Constants for H2 + O2 yields H + HO2 at High Temperature

Descriptive Note:

Conference paper

Corporate Author:

ARGONNE NATIONAL LAB IL CHEMISTRY DIV

Personal Author(s):

• Michael, J. V.
• Sutherland, J. W.
• Harding, L. B.
• Wagner, A. F.

Report Date:

2000-08-04

Pagination or Media Count:

5.0

Abstract:

The reaction between H2 and O2 has been studied in a reflected shock tube apparatus between temperatures of 1662 - 2097 K and pressures of 400 - 570 torr with Kr as the diluent gas. O atom atomic resonance absorption spectrometry ARAS was used to observe absolute Osub t under conditions of low H2sub 0 so that most secondary reactions were negligible. Hence, the observed Osub t was the direct result of the rate controlling reaction between H2 and O2. Three different reactions were considered, but experimental and ab initio theoretical results both indicated that the process, H2 O2 - H HO2, is the most probable reaction. After rapid HO2 dissociation, O atoms are then instantaneously produced by H O2 - O OH. Using the ab initio result, conventional transition state theoretical calculations CTST with tunneling corrections give the expression kth1 1.288 X 10-18 T2.4328 exp-26,926 KT cu cm molecule-1 s-1, applicable between 400 and 2300 K. This theoretical result agrees with the present experimental determinations and those at lower temperature, derived from earlier work on the reverse reaction.

Descriptors:

• *HYDROGEN
• *OXYGEN
• *RECOMBINATION REACTIONS
• MATHEMATICAL MODELS
• HYDROXIDES
• SHOCK TUBES
• OXIDATION
• SYMPOSIA
• WATER

Subject Categories:

• Physical Chemistry
• Operations Research
• Combustion and Ignition

Distribution Statement:

APPROVED FOR PUBLIC RELEASE