Studies with a Single-Pulse Shock Tube. II. The Thermal Decomposition of Perfluorocyclobutane

Abstract

The thermal decomposition of perfluorocyc1obutane was studied behind reflected shocks in a single-pulse shock tube over the temperature range 1040 o -1200oK. Mixtures of approximately 1% to 1.5% of perfluorocyclobutane in argon were used. The reaction products were analyzed by vapor-phase chromatography. The first-order rate constants obtained at high temperatures are slightly higher than the values deduced from an Arrhenius extrapolation of the low-temperature data; however, the activation energy is the same. The rate constant is: kuni"'=2.1X10 16 exp[ -74.3X10 3 /RT]'

Chain elongation during thermolysis of tetrafluoroethylene and hexafluoropropylene: Modeling of mechanistic hypotheses and elucidation of data needs

“…The absence of reliable thermochemical parameters for the C 4 F 8 isomers (see below) precludes any thermodynamic hypothesis concerning the apparent temperature dependence of their ratio. Cycloreversion of c-C 4 F 8 was observed under shock-tube conditions at 770-930 • C [32,33] and at 825-990 • C [34], as well as under adiabatic compression conditions at 725-875 • C [5]. Data from Bauer and Javanovic [20] on the formation of C 2 F 4 and C 3 F 6 in a micro-pilot plant in the 800 • C range were subject to significant fluctuations in temperature and pressure during reaction.…”

Kinetics of methyl iodide-iodine exchange in a shock tube

“…To make the cooling the most efficient the length of the driver section is adjusted such that the reflected far-end expansion wave coincides with the expansion wave formation at the point C, resulting in their reinforcement. This results in a rapid cooling, determined in several cases by Lifshitz et al (17,19) as 10^ deg./sec., although it is by no means as rapid as the heating. All the significant reaction thus takes place in the slashed region 5.…”

Boundary Layer Effects on Chemical Kinetics Studies in a Shock Tube

“…Lifshitz et al 4 found kunt'= 10 16 . THE TEST REACTION: C 4 Fg-t2C 2 F 4 As a test reaction the decomposition of PFCB was studied.…”