FTIR study of the Cl- and Br-atom initiated oxidation of trichloroethylene

✍ Scribed by V. Catoire; P. A. Ariya; H. Niki (Deceased); G. W. Harris

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 198 KB
• Volume: 29
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/(sici)1097-4601(1997)29:9<695::aid-kin7>3.0.co;2-p

✦ Synopsis

The Cl-and Br-initiated oxidations of CHCl"CCl 2 in 700 torr of air at 296 K have been studied using a Fourier transform infrared spectrometer. Rate constants k(Cl ϩ and

were determined using a relative rate technique with ethane and ethylene as Ϫ 1 Ϫ 1 molecule s references, respectively. The major products observed were CHXClC(O)Cl, (X ϭ Cl or Br), CHClO, and CCl 2 O. Combining results obtained for the Cl-initiated oxidation of CHCl 2 9CHCl 2 , we deduced that Cl-addition on trichloroethylene occurs via channel 1a, Cl ϩ Self-reaction of the subsequently generated per-CHCl"CCl : CHCl 9 CCl , (100 Ϯ 12)%. 2 2 2 oxy radicals CHCl 2 9 CCl 2 O 2 leads to CHCl 2 CCl 2 O radicals which were found to decompose via channel 8a, of the time, and channel 8b, CHCl C(O)Cl ϩ Cl, (91 Ϯ 11)% CHCl ϩ 2 2 The reaction (17a) accounted for CCl O, (9 Ϯ 2)%. Br ϩ CHCl" CCl : CHBrCl9CCl 2 2 2 of the total reaction. Decomposition of the CHBrCl9CCl 2 O radicals proceeds Ն(96 Ϯ 11)% via As part of this work, (Ն93 Ϯ 11)% CHBrClC(O)Cl ϩ Cl. k(Cl ϩ CHCl C(O)Cl) ϭ (3.6 Ϯ 2 and were mea-Ϫ 14 Ϫ 13 3 Ϫ 1 Ϫ 1 0.6) ϫ 10 k(Cl ϩ CHCl 9CHCl ) ϭ (1.9 Ϯ 0.2) ϫ 10 cm molecule s 2 2 sured. Errors reported above include statistical uncertainties (2) and estimated systematic uncertainties.