Shock-Tube Measurement of Acetone Dissociation Using Cavity

Feb 6, 2015 - Shock-Tube Measurement of Acetone Dissociation Using Cavity-Enhanced Absorption Spectroscopy of CO ... Fax: +1-(650)-723-1748. ... A dir...
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Article pubs.acs.org/JPCA

Shock-Tube Measurement of Acetone Dissociation Using CavityEnhanced Absorption Spectroscopy of CO Shengkai Wang, Kai Sun, David F. Davidson,* Jay B. Jeffries, and Ronald K. Hanson High Temperature Gasdynamics Lab, Mechanical Engineering, Stanford University, Bldg. 520, Duena Street, Stanford, California 94305, United States ABSTRACT: A direct measurement for the rate constant of the acetone dissociation reaction (CH3COCH3 = CH3CO + CH3) was conducted behind reflected shock wave, utilizing a sub-ppm sensitivity CO diagnostic achieved by cavity-enhanced absorption spectroscopy (CEAS). The current experiment eliminated the influence from secondary reactions and temperature change by investigating the clean pyrolysis of 99.999% purity, supplied by Praxair).

The gas mixtures were prepared manometrically in a 40 L stainless-steel mixing tank, which was preheated to 50 °C to prevent wall condensation. The mixing process was accelerated C

DOI: 10.1021/jp511642a J. Phys. Chem. A XXXX, XXX, XXX−XXX

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The Journal of Physical Chemistry A by a magnetic stirrer, and typical mixing time was at least 2 h to ensure the mixture homogeneity. Mixtures with low acetone concentrations (