TY - JOUR

T1 - UV absorption spectra, kinetics and mechanism for alkyl and alkyl peroxy radicals originating from t-butyl alcohol

AU - Langer, Sarka

AU - Ljungström, Evert

AU - Sehested, Jens

AU - Nielsen, Ole J.

PY - 1994/8/12

Y1 - 1994/8/12

N2 - Alkyl and alkyl peroxy radicals from t-butyl alcohol (TBA), HOC(CH3)2CH2{radical dot} and HOC(CH3)2CH2O2{radical dot} have been studied in the gas phase at 298 K. Two techniques were used: pulse radiolysis UV absorption to measure the spectra and kinetics, and long path-length Fourier transform infrared spectroscopy (FTIR) to identify and quantify the reaction products. Absorption cross sections were quantified over the wavelength range 220-320 nm. At 240 nm, σHOC(CH3)2CH2=(2.4 ±0.3)×10-18 and σHOC(CH3)2CH2O2 =(3.4±0.5)×10-18 cm2 molecule-1 have been obtained. Observed rate constants for the self-reaction of HOC(CH3)2CH2{radical dot} and HOC(CH3)2CH2O2{radical dot} radicals were found to be (3.0±0.5)×10-11 and (7.8±1.5)×10-12 cm3 molecule-1 s-1, respectively. For the reaction of the alkyl radical with O2 in 1 atm SF6 a rate constant of (1.8±0.2)×10-12 cm3 molecule-1 s-1 was found. k(HOC(CH3)2CH2O2{radica l dot}+NO) and k(HOC(CH3)2CH2O2{radica l dot}+NO2) were determined to be (4.9±0.9)×10-12 and (6.7±0.9)×10-12 cm3 molecule -1 s-1, respectively. In the FTIR experiments products were studied using chlorine-initiated oxidation in TBA/N2/Cl2 and TBA/N2/O2/Cl2 mixtures.

AB - Alkyl and alkyl peroxy radicals from t-butyl alcohol (TBA), HOC(CH3)2CH2{radical dot} and HOC(CH3)2CH2O2{radical dot} have been studied in the gas phase at 298 K. Two techniques were used: pulse radiolysis UV absorption to measure the spectra and kinetics, and long path-length Fourier transform infrared spectroscopy (FTIR) to identify and quantify the reaction products. Absorption cross sections were quantified over the wavelength range 220-320 nm. At 240 nm, σHOC(CH3)2CH2=(2.4 ±0.3)×10-18 and σHOC(CH3)2CH2O2 =(3.4±0.5)×10-18 cm2 molecule-1 have been obtained. Observed rate constants for the self-reaction of HOC(CH3)2CH2{radical dot} and HOC(CH3)2CH2O2{radical dot} radicals were found to be (3.0±0.5)×10-11 and (7.8±1.5)×10-12 cm3 molecule-1 s-1, respectively. For the reaction of the alkyl radical with O2 in 1 atm SF6 a rate constant of (1.8±0.2)×10-12 cm3 molecule-1 s-1 was found. k(HOC(CH3)2CH2O2{radica l dot}+NO) and k(HOC(CH3)2CH2O2{radica l dot}+NO2) were determined to be (4.9±0.9)×10-12 and (6.7±0.9)×10-12 cm3 molecule -1 s-1, respectively. In the FTIR experiments products were studied using chlorine-initiated oxidation in TBA/N2/Cl2 and TBA/N2/O2/Cl2 mixtures.

UR - http://www.scopus.com/inward/record.url?scp=0013616776&partnerID=8YFLogxK

U2 - 10.1016/0009-2614(94)00691-1

DO - 10.1016/0009-2614(94)00691-1

M3 - Journal article

AN - SCOPUS:0013616776

VL - 226

SP - 165

EP - 170

JO - Chemical Physics Letters

JF - Chemical Physics Letters

SN - 0009-2614

IS - 1-2

ER -