Product formation from the reaction of the NO3 radical with isoprene and rate constants for the reactions of methacrolein and methyl vinyl ketone with the NO3 radical

✍ Scribed by Eric S. C. Kwok; Sara M. Aschmann; Janet Arey; Roger Atkinson

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 707 KB
• Volume: 28
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/(sici)1097-4601(1996)28:12<925::aid-kin10>3.0.co;2-b

✦ Synopsis

Using a relative rate method, rate constants for the gas-phase reactions OF the NO, radical with methacrolein and methyl vinyl ketone were determined to be ( 4 4 2 1.7) X cm' molecule-' s-' and < 6 X cm3 molecule-' S S ' , respectively, at 296 ? 2 K. The molar formation yields of rnethacrolein and methyl vinyl ketone from the gas-phase reaction of the NO, radical with isoprene at 296 ? 2 K and atmospheric pressure of air were measured to be 0.035 ? 0.014 each The tropospheric implications of these kinetic and product data are discussed, and it is concluded that the nighttime NO, radical reactions with methacroiein and methyl vinyl ketone are not important. However, during nighttime the formation of methacrolein and methyl vinyl ketone from the reaction of isoprene with the NO, radical may dominate over their formation from the 0, reaction with isoprene. Atmospheric pressure ionization tandem mass spectrometry (API-MS/MS) was used to investigate the products of the reactions of the NO, radical with isoprene and isoprene-d,, and C,-nitrooxycarbonyl(s) ( e g , O,NOCH,C(CH,)=CHCHO). C,-hydroxynitrate(s) ( e g , O,NOCH,C(CH,)=CHCH,OHI, C,nitrooxyhydroperoxide(s) (e g., 0,NOCH2C(CH, I=CHCH,OOH), and C,-hydroxycarbonyl(s1 l e g , HOCH,CH=C(CH,)CHO) and their deuterated analogs were observed from these reactions