Rates and mechanisms of the reactions of ethanol and propanol with fluorine and chlorine atoms

Abstract

The reactions of C2H5OH (1), C2H5OD (2), C2D5OD (3), 1‐C3H7OH (4), 2‐C3H7OH (5), 2‐C3H7OD (6) with F atoms and the reactions of C2H5OH (7), 1‐C3H7OH (8), 1‐C3H7OD (9), 2‐C3H7OD (10) with Cl atoms have been studied in a discharge flow reactor and a Laval nozzle reactor at room temperature and at pressures of a few mbar. Samples of the reaction mixtures were withdrawn continuously by a molecular beam device and analyzed by a mass spectrometer. The rates of the reactions were measured relative to the standard reactions C2H6 + F (0) and C2H6 + Cl (00) yielding k1/k0 = 1.06, k2/k0 = 1.25, k3/k0 = 1.20, k4/k0 = 1.26, k5/k0 = 1.06, k6/k0 = 1.20, k7/k00 = 2, k9/k00 = 4. For the reactions of F atoms with alcohols the probability of attack at one of the alkyl H atoms was found to be five times less than at the hydroxyl H atom site. For the reactions of Cl atoms with alcohols no abstraction from the OH group was observed, the abstraction from the alkyl groups follows the thermodynamically favoured route by forming mainly secondary radicals.

Kinetics of the Reactions of Cl*(2P1/2) and Cl(2P3/2) Atoms with CH3OH, C2H5OH, n-C3H7OH, and i-C3H7OH at 295 K

“…For the Cl + n-C 3 H 7 OH reaction, it has been suggested that H atoms at both the R-and -positions are abstracted. 6 The trend k reac (Cl( 2 P 3/2 ) + CH 3 OH) < k reac -(Cl( 2 P 3/2 ) + C 2 H 5 OH) ≈ k reac (Cl( 2 P 3/2 )+i-C 3 H 7 OH) < k reac (Cl-( 2 P 3/2 )+n-C 3 H 7 OH) follows the trend of exothermicity values listed in Table 1 for H-atom abstraction from the R-position; that is, ∆H R (Cl+CH 3 OH) > ∆H R (Cl+C 2 H 5 OH) ≈ ∆H R (Cl+i-C 3 H 7 OH) > ∆H R (Cl+n-C 3 H 7 OH). Table 3, chemical reaction accounts for 18-34% of the total removal of Cl* in collisions with CH 3 OH, C 2 H 5 OH, n-C 3 H 7 OH, and i-C 3 H 7 OH.…”

The Reactions of the Cyclic Hydrocarbon Radicals c‐C3H5, c‐C5H9, and c‐C6H11 with O Atoms in the Gas Phase

“…to 14, k 2 = 1.7.10 14 cmvrnol s). The rate constant k 3 has been measured in this study with reference to the reaction Adopting the averaged rate constant k o = 1.2·t0 14 cm 3 1 mol· s from the literature (see [10]) this gives k 3 = 5.7 . The ring structure of the radicals are maintained in the reactions (1) -(3).…”

Rate constant for the reaction of F‐atoms with trichloroacetic acid

“…Also, it was desired to work with a reactant that could be detected by its molecular mass‐spectral peak. Based on these criteria, the reaction with ethanol has been chosen: for which only one measurement k 4 (298 K) = 1.28 × 10 −10 cm 3 molecule −1 s −1 , was reported by Khatoon et al . This value was obtained by the relative rate method using reference reaction : for which the ratio k 4 / k 5 = 1.06 (± 0.006) was determined.…”

“…The authors of Ref. did not give any estimation of the uncertainty in k 4 , and, since the k 4 / k 5 ratio was measured with very high accuracy, this uncertainty was solely determined by k 5 . The rate constant k 5 = 1.21 × 10 −10 cm 3 molecule −1 s −1 was taken from the earlier study of Khatoon and Hoyermann, where it was measured relative to the reaction with methane: with the ratio k 5 / k 6 = 1.83.…”

“…for which only one measurement k 4 (298 K) = 1.28 × 10 −10 cm 3 molecule −1 s −1 , was reported by Khatoon et al 19 This value was obtained by the relative rate method using reference reaction (5):…”