Kinetics of gas-phase fluorination of halomethanes

Abstract

The rates of the hydrogen abstraction rections of fluorine atoms with five halomethanes and two alkanes in the gas phase were studied using competitive methods. The main competitors were arranged in the following series in which adjacent pairs were fluorinated competitively :

Experimental and theoretical investigation of the reaction of RO2 radicals with OH radicals: Dependence of the HO2 yield on the size of the alkyl group

“…Therefore, from the HO 2 profiles under low O 2 (both isomers lead to HO 2 ) and under high O 2 (only the peroxy from 2‐C 4 H 9 radical from (R3) leads to a second HO 2 ) one can deduce the ratio of formation of 1‐ and 2‐C 4 H 9 in (R3). HO 2 profiles are best reproduced for C 4 H 10 , if 1‐C 4 H 9 is produced in 1.3‐fold excess over 2‐C 4 H 9 , in excellent agreement with earlier measurements by Foon and McAskill …”

“…The ratio of the formation of the different isomers has been determined to be 1‐C 3 H 7 /2‐C 3 H 7 = 2.3 [Ref. ] and 1‐C 4 H 9 /2‐C 4 H 9 = 1.3 …”

Gas Phase Reactions of Fluorine Atoms

“…The data from CHF, is plotted in Fig. 4 according to [15]. We conclude from the linearity of the plot that reactions which are second order in radical concentrations, [ l l ] and [12], do not contribute to the removal of R and F, and that steps [I]- [5], [7], and [8] For personal use only.…”

“…Relative rate determinations by measurement of the total chemiluminescence of H F (12) and product analysis (13)(14)(15)(16)(17) have extended the range of compounds to C,-C, alkanes (13,14,16) as well as the chlorinated C, and C, hydrocarbons and fluorocarbons (15)(16)(17). Complementing these determinations of the overall rate constants have been the studies designed to elucidate the relative populations of the various vibrational levels of the product H F (12,(18)(19)(20)(21).…”

Reaction Kinetics of Ground State Fluorine, F(2P), Atoms. I. Measurement of Fluorine Atom Concentrations and the Rates of Reactions F + CHF3 and F + Cl2 using Mass Spectrometry

“…The scatter of these results is typical of the whole series of rate measurements described in this section. No detailed discussion is given of the present values for these rate constants, k,,,, in relation to existing data (1)(2)(3)(4)21) except to note that no anomalies are now apparent, within the admittedly wide range of all the data. The relative values of Ic,, generally agree satisfactorily with those based upon competitive fluorination studies (4,22 Table 3 shows a summary of these data, together with the corresponding values of AVO,,,.…”