UV absorption spectra and kinetics for alkyl and alkyl peroxy radicals originating from di-tert-butyl ether

✍ Scribed by Ole J. Nielsen; Jens Sehested; Sarka Langer; Evert Ljungström; Ingvar Wängberg

• Book ID: 103033327
• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 345 KB
• Volume: 238
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(95)00401-o

✦ Synopsis

Alkyl, (CH3)3COC(CH3)2CH2, and alkyl peroxy, (CH3)3COC(CH3)2CH202, radicals from di-tert-butyi ether (DTBE), have been studied in the gas phase at 296 K. A pulse radiolysis UV absorption technique was used to measure the spectra and kinetics. Absorption cross sections were quantified over the wavelength range 220-330 nm. At 240 nm, O' <CH3)3COC(CH3)2CH: = (3.6 + 0.4) × 10 -18 cm 2 molecule-1 and at 260 nm, O'(CH3hCOC(CH3):CH20: = (3.8 _+ 0.3) × 10 -t8 cm 2 molecule-1 have been obtained. The observed rate constants for the self-reaction of (CH3)aCOC(CH3)2CH 2 and (CH3)aCOC(CH3)ECH202 radicals were found to be (2.9 +_ 0.2) × 10 -11 cm 3 molecule -1 s -1 and (2.7 _+ 0.2) × 10 -12 cm 3 molecule-x s-1, respectively. For the reaction of the alkyl radical with O e in 1 atm pressure of SF 6 a rate constant of (7.2 _+ 1.1)× 10-13 cm 3 molecule-1 s-1 was found. The rate constants for the reaction of the alkyl peroxy radicals with NO and NO 2 were determined to be (1.8 _+ 0.2) × 10 -12 and (9.9 _+ 1.3) × 10 -12 cm 3 molecule -1 s -i, respectively. As a part of the work the rate constants k(F + DTBE) and k(OH + DTBE) were determined to be (2.6 _+ 0.6) × 10-10 and (4.0 _ 0.9) × 10 -12 cm 3 molecule-x s-1, respectively.