A relative rate study of the reaction of chlorine atoms (Cl) and hydroxyl radicals (OH) with a series of ethers

Abstract

Rate constants for the gas phase reactions of hydroxyl radicals and chlorine atoms with a number of ethers have been determined at 300 2 3 K and at a total pressure of 1 atmosphere. Both OH radical and chlorine atom rate constants were determined using a relative rate technique. Values for the rate constants obtained are as follows. CompoundHexane 5.53 2 1.55 2 4.4The above relative rate constants are based on the values of k(OH + pentane) = [3.94 2 0.981 X lo-'' and k(OH + diethyl ether) = [13.6 2 2.263 X lo-'' cm3 molecule-' s-l in the case of the hydroxyl reactions. In the case of the chlorine atom reactions, the above rate constants are based on values of k(C1 + ethane) = f5.84 2 0.881 X lo-" and k(C1 + diethyl ether) = L25.4 2 8.053 X lo-" cm3 molecule-' s-'. The quoted errors include 2 2 u from a least squares analysis of our slopes plus the uncertainty associated with the reference rate constants.Atmospheric lifetimes calculated with respect to reaction with OH radicals are based on a tropospheric OH radical concentration of (7.7 2 1.4) x lo5 radicals ~m -~, and lifetimes with respect to reaction with C1 atoms are based on a tropospheric C1 atom concentration of 1 x lo3 atoms ~m -~. Observed trends in the relative rates of reaction of hydroxyl radicals and chlorine atoms with the ethers studied is discussed. The significance of the calculated tropospheric lifetimes is also reviewed. 0 1993 John Wiley & Sons, Inc.

Rate constants for the gas‐phase reactions of Cl atoms with a series of ethers

“…: RЉCl ϩ Cl 2 Table I), and our final results are obtained from the combination of the results obtained at 15 and 60 Torr. While a good agreement is observed with the rate constant values reported in this work; those obtained by Nelson et al [8] for DME, DEE, DPE, DBE, and DIPE; and those of McLoughlin et al [10] for DEE and DIPE, one could observe a disagreement with the data reported by Wallington et al [7] for DME and DEE. In all cases the data show good linearity.…”

Kinetics of the gas-phase reactions of OH radicals with alkanes and cycloalkanes

“…In the temperature range 292-390 K the agreement between the absolute and relative rate studies is good. The room temperature relative rate data of Atkinson et al (1983a), , Behnke et al (1987Behnke et al ( , 1988 and McLoughlin et al (1993), which are not shown in the Arrhenius plot in Fig. 11, are also in good agreement with these data of Atkinson et al (1982a), Klein et al (1984), Donahue et al (1998) and DeMore and Bayes (1999).…”

Rate constants for the gas-phase reactions of Cl atoms with a series of ethers

“…The other measurements were performed using the relative rate technique. While a good agreement is observed with the rate constant values reported in this work; those obtained by Nelson et al [8] for DME, DEE, DPE, DBE, and DIPE; and those of McLoughlin et al [10] for DEE and DIPE, one could observe a disagreement with the data reported by Wallington et al [7] for DME and DEE. The measurements of Wallington et al were done relative to that of n-butane using k(Cl ϩ n-C 4 H 10 ) ϭ 2.25 ϫ 10 Ϫ10 cm 3 molecule Ϫ1 s Ϫ1 .…”