Atmospheric chemistry of ketones: Reaction of OH radicals with 2-methyl-3-pentanone, 3-methyl-2-pentanone and 4-methyl-2-pentanone

This work reports new kinetic and mechanistic information on the atmospheric chemistry of ketones. Both absolute relative rate methods were used to determine constants for OH reactions with 2-methyl-3-pentanone (2M3P), 3-methyl-2-pentanone (3M2P) 4-methyl-2-pentanone (4M2P), three widely compounds in industry. constitutes first temperature dependence study 2M3P 3M2P. The following values are recommended at 298 K (in 10 −12 cm 3 molecule −1 s ): k OH+2M3P = 3.49 ± 0.5; OH+3M2P 6.02 0.14 OH+4M2P 11.02 0.42. Arrhenius expressions units ) adequately describe measured 3M2P range 263–373 K: (2.33 0.06) × exp((127.4 18.6)/T) (1.05 0.14) exp((537 41)/T). Products studies from investigated ketones conducted a 7.3 m simulation chamber using PTR-ToF-MS, UHPLC-MS GC–MS. A series short chain carbonyl including formaldehyde, acetone, acetaldehyde, 2-butanone 2-methypropanal observed as products. Combining yields carbonyls those estimated SAR method, we propose various degradation schemes initiated by reaction radicals. • Room determined 2M3P, 4M2P radicals; 3M2P; OH-initiated oxidation products studied have been under conditions; Mechanistic proposed mainly based experimental data; enabled discuss fate