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Disproportionation-combination rate constant ratios for haloalkyl radicals: Evidence for heterogeneous disproportionation

✍ Scribed by Bert E. Holmes; David J. Rakestraw

Publisher: John Wiley and Sons
Year: 1987
Tongue: English
Weight: 711 KB
Volume: 19
Category: Article
ISSN: 0538-8066
DOI: 10.1002/kin.550190503

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✦ Synopsis

Disproportionation-combination rate constant ratios, kd / k c , have been determined for R + RCH,CHCl and for the auto disproportionation-combination of RCH2CHC! radicals, R = CF3, C,F,, and C3F7. The k d / k , for R = CF, and to a lesser degree for R = C,F, and C,F, were very sensitive to the surface/volume ratio of the reaction vessel suggesting a heterogeneous component for disproportionation.

Stefani found that kd/k, declined with increasing volume of the reaction cell but the kd/k, were based solely on the C,H, yield.

We wish to report measurement of disproportionation-combination rate constant ratios, &/kc, for R + RCHzCHCl and for the auto disproportionation of RCH,CHCl (R = CF3, C2F5, and C3F7) in which the surface/volume ratio (S/V) of the vessel dramatically altered the kd /kc values for R = CF, and gave a smaller, but noticeable effect, for

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