A critical review of the kinetics of the dissociation‐recombination reactions of fluorine and chlorine

Abstract

A critical evaluation of the rates of the dissociation and recombination reactions of fluorine and chlorine'is given.The effect of various third bodies is discussed. Rate expreaions for specified temperature ranges are recommended, while comparison with theoretical values obtained from the Benson and Fueno theory is made where applicable.Data are presented graphically and in tabular form.

Direct study of the catalytic decomposition of chlorine and chloromethanes over carbon films

“…From the Lennard-Jones collision rate constant ZLJ(Ar + Cl,) = 2.93 x 1014 cm3 mol-' s-' at 1300 K [231, we calculate the equivalent argon concentration: nAr = o/ZLJ = 3.82 x lo-'' mol cm-3 at which the argon-chlorine and chlorine-wall collision frequency w would be identical. Using this value of nAr and kd(Ar + C1,) = 6.16 X lo5 cm3 mol-' s-' at 1300 K [24] we obtain a pseudofirst-order rate constant for the decomposition of chlorine over hot silica: k d ( S -l ) = 2. 36 X 10-4(p,/p,,), where (p,/pAr) the ratio of collision efficiencies should have a value between 1 and 10 [24,251.…”

High-temperature chemistry of HCl and Cl2

“…The early measurements of Hiraoka and Hardwick [92] and Diesen and Felmlee [93] indicate values of k 9b an order of magnitude higher than the bulk of the data. The high values have been attributed to boundary layer effects and limitations in detection accuracy and were disregarded by both Lloyd [91] and Baulch et al [30]. The data from Jacobs and Giedt [94], van Thiel et al [95], and Carabetta and Palmer [96] are in good agreement and these data form the basis for the recommendation of Lloyd [91].…”

“…The results were evaluated by Lloyd [91] and Baulch et al [30]. The high temperature data fall in three groups.…”

“…The high values have been attributed to boundary layer effects and limitations in detection accuracy and were disregarded by both Lloyd [91] and Baulch et al [30]. The data from Jacobs and Giedt [94], van Thiel et al [95], and Carabetta and Palmer [96] are in good agreement and these data form the basis for the recommendation of Lloyd [91]. The third group of data, reported by Blauer et al [97] and Santoro et al [98], indicate a rate constant for Cl + Cl + Ar that is about a factor of five below the bulk data.…”

The mechanism of the H2 + CL2 reaction: Ignition behind reflected shocks

“…Since in this reaction scheme there is no branching involved, the induction time is very sensitive to the rate of the initiation reaction, i.e., to the rate of the dissociation of chlorine. This reaction was studied extensively by a great number of investigators and has been recently summarized in a review article [9]. Rate constants are available for Ar, CIS, and C1 as third bodies.…”