Investigation of kinetics and mechanistic insights of the reaction of criegee intermediate (CH2OO) with methyl-ethyl ketone (MEK) under tropospherically relevant conditions

Temperature-Dependent Kinetics of the Reactions of the Criegee Intermediate CH2OO with Hydroxyketones

“…The rate constant for the CH 2 OO + acetone (Ac) 11,12,21,22 The rate constant for the CH 2 OO + methylethylketone (MEK) reaction is slightly larger than that of Ac with a value k MEK = 6.4 × 10 −13 cm 3 s −1 . 70 The room temperature rate constants for the hydroxyketone reactions are much closer to that of acetaldehyde (MeCHO), for which rate constants in the range k MeCHO = (1.0−1.7) × 10 −12 cm 3 s −1 have been reported. 19,20,23 The CH 2 OO + R 1 R 2 CO reactions also all show similar negative temperature dependences.…”

Experimental and theoretical study of Criegee intermediate (CH2OO) reactions with n-butyraldehyde and isobutyraldehyde: kinetics, implications and atmospheric fate

“…The k exp value is taken from a previous study. 36 The k pseudo is the pseudo-1st order rate coefficient for the reaction (R4) or (R5), Δ κ 0 and Δ κ t are the decay coefficients at reaction time 0 and t , respectively, and c is the speed of light under vacuum. The exponential decay plots of CH 2 OO on reaction with n BD and iBD at room temperature are given in Fig.…”

“…A custom-built CRDS setup was used in this experiment, which is described in our previous publication. 36 Only the necessary points will be discussed here. The photolysis of the CH 2 I 2 was carried out in a double-jacketed Pyrex cell by 355 nm pulsed UV-radiation (100 mJ pulse À1 ) from a frequency tripled Nd:YAG laser (Litron LPY Series) in the presence of O 2 to generate CH 2 OO.…”

“…The involvement of these species was neglected due to either their low absorption cross-section or by employing appropriate reaction conditions, which is discussed thoroughly in the ESI† of a previous study. 36 The ring-down profiles were digitized by a data acquisition system and analyzed after averaging the signals for every 20 pulses in a PC using a custom-made LabVIEW program.…”

“…4,15,[28][29][30] The kinetics of CH 2 OO with carbonyl compounds were found to be interesting due to their large dependence on pressure and temperature, mainly because of the 1,3-cycloaddition of the CH 2 OO to the CQO group of the carbonyl compounds. 26,[31][32][33][34][35][36] Aldehydes are one of the classes of oxygenated volatile organic compounds (OVOC), which are responsible for urban air pollution, and act as precursors for SOA, tropospheric ozone and even fine particulate matter (PM 2.5 ). [37][38][39][40] Aldehydes are released into the atmosphere from primary and secondary sources.…”