The kinetics and mechanism of an aqueous phase isoprene reaction with hydroxy radical D. Huang, X. Zhang, Z. M. Chen, Y. Zhao and X. L. Shen State Key Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China Supplementary material Table S1. Mechanisms for the OH oxidation of isoprene in the box model. Fig. S1. Time series of products in the aqueous isoprene-oh reaction under the condition of 1.5 L top space in the.1 L reactor. Fig.S. Experiments 1 and (green and blue) for the kinetics of aqueous OH-initiated oxidation of isoprene (ISO), methacrolein (MACR), and methyl vinyl ketone (MVK) relative to salicylic acid at 8 K. (a) ISO/SA; (b) MACR/SA; (c) MVK/SA. Correspondence to: Z.M. Chen (zmchen@pku.edu.cn)
Table S1. Mechanisms for the OH oxidation of isoprene in the box model. Initial Adjusted Rate Rate NO Reaction constant constant (M -1 s -1 ) (M -1 s -1 ) 1 O + hv OH H. 10-5 (s -1 ). 10-5 (s -1 ) O + OH HO H O.7 10 7.7 10 7 H + HO + H O H O + O + OH.7.7 4 HO + HO H O + O 8. 10 5 8. 10 5 isoprene + OH R1O 1.8 10 9 1.8 10 9 5 isoprene + OH RO 5.4 10 9 5.4 10 9 6 isoprene + OH RO 6.0 10 8 6.0 10 8 7 isoprene + OH R4O 6.0 10 8 6.0 10 8 8 isoprene + OH R5O 9.6 10 8 9.6 10 8 9
10 isoprene + OH R6O.6 10 9.6 10 9 11 R1O + R1O R1O + R1O + O 1.4 10 8 1.4 10 8 1 RO + RO RO + RO + O 4. 10 6 4. 10 8 1 RO + RO RO + RO + O 1.7 10 8 1.7 10 8 14 R4O + R4O R4O + R4O + O 1.7 10 8 1.7 10 8 15 R5O + R5O R5O + R5O + O 1.0 10 8 1.0 10 8 16 R6O + R6O R6O + R6O + O.8 10 8.8 10 8 17 R1O + RO R1O + RO + O 1. 10 8.0 10 8 18 R1O + RO R1O + RO + O 1.7 10 8 1.7 10 8 19 R1O + R4O R1O + R4O + O 1.7 10 8 1.7 10 8 0 R1O + R5O R1O + R5O + O 1. 10 8 1. 10 8 1 R1O + R6O R1O + R6O + O 1.7 10 8 1.7 10 8 RO + RO RO + RO + O 1. 10 8. 10 8
RO + R4O RO + R4O + O 1. 10 8. 10 8 4 RO + R5O RO + R5O + O 1. 10 8. 10 8 5 RO + R6O RO + R6O + O 1.7 10 8.6 10 8 6 RO + R4O RO + R4O + O 1.7 10 8 1.7 10 8 7 RO + R5O RO + R5O + O 1. 10 8 1. 10 8 8 RO + R6O RO + R6O + O. 10 8. 10 8 9 R4O + R5O R4O + R5O + O 1. 10 8 1. 10 8 0 R4O + R6O R4O + R6O + O. 10 8. 10 8 1 R5O + R6O R5O + R6O + O 1.7 10 8 1.7 10 8 R1O + R1O 9. 10 7 9. 10 7 RO + RO 1. 10 8 1. 10 8 4 R4O + R4O 1. 10 8 1. 10 8 5 R5O + R5O 6.5 10 7 6.5 10 7
6 R6O + R6O 6.9 10 7 6.9 10 7 7 R1O + RO.9 10 7 4.0 10 7 8 R1O + RO 1.1 10 8 1.1 10 8 9 R1O + R4O 1.1 10 8 1.1 10 8 40 R1O + R5O 7.7 10 7 7.7 10 7 41 R1O + R6O 7.0 10 7 7.0 10 7 4 RO + RO.1 10 7 5.7 10 7 4 RO + R4O.1 10 7 5.7 10 7 44 RO + R5O.9 10 7 5. 10 7 45 RO + R6O 1.9 10 7.5 10 7 46 RO + R4O 1. 10 8 1. 10 8 47 RO + R5O 8.7 10 7 8.7 10 7 48 RO + R6O 9. 10 7 9. 10 7
49 R4O + R5O 8.7 10 7 8.7 10 7 50 R4O + R6O 9. 10 7 9. 10 7 51 R5O + R6O 7.0 10 7 7.0 10 7 5 R1O + HO R1OOH + O 9.8 10 8 9.8 10 8 5 RO + HO ROOH + O 9.8 10 8 9.8 10 8 54 RO + HO ROOH + O 9.8 10 8 9.8 10 8 55 R4O + HO R4OOH + O 9.8 10 8 9.8 10 8 56 R5O + HO R5OOH + O 9.8 10 8 9.8 10 8 57 R6O + HO R6OOH + O 9.8 10 8 9.8 10 8 58 MVKAOO + R1O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 59 MVKAOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 60 MVKAOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 61 MVKAOO + R4O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6
6 MVKAOO + R5O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 6 MVKAOO + R6O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 64 MVKBOO + R1O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 65 MVKBOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 66 MVKBOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 67 MVKBOO + R4O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 68 MVKBOO + R5O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 69 MVKBOO + R6O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 70 MACRAOO + R1O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 71 MACRAOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 7 MACRAOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 7 MACRAOO + R4O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 74 MACRAOO + R5O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6
75 MACRAOO + R6O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 76 MACRBOO + R1O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 77 MACRBOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 78 MACRBOO + RO 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 79 MACRBOO + R4O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 80 MACRBOO + R5O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 81 MACRBOO + R6O 0. * MACR + 0. * MVK + 0.6 * MG + HCHO + 1. * HO.0 10 6.0 10 6 8 R1O H8O. 10 5. 10 5 8 R5O H8O. 10 5. 10 5 84 R1OOH+ OH H8O + OH 6.4 10 9 6.4 10 9 85 R5OOH+ OH H8O + OH 6.4 10 9 6.4 10 9 86 R1OOH H8O + HO + OH 5.8 10-6 5.8 10-6 87 R5OOH H8O + HO + OH 5.8 10-6 5.8 10-6
88 89 90 91 9 C5H8O + OH 0.5 * C5H9O5.7 10 9.7 10 9 C H9O5 0.7* MG 0.7* GL 1. 10 4 1. 10 4 5 + C5H9O5 + HO H9O5H 1. 10 9 1. 10 9 C5H9O5H + OH H9O5 1.9 10 9 1.9 10 9 C5 9 5 + H O H 0.5* MG 0.5* GL 5.8 10-6 5.8 10-6 9 R1O + O carbonyl + HO 1.0 10 5 1.0 10 5 94 R1O carbonyl + HO 1.0 10 5 1.0 10 5 95 RO + O MVK + HCHO + HO 7.5 10 4 7.5 10 4 96 RO MVK + HCHO + HO 7.5 10 4 7.5 10 4 97 RO + O HMVK + CHO.5 10 4.5 10 4 98 RO HMVK+ CH O.5 104.5 10 4 99 RO + O MVK + HCHO + HO 5.0 10 4 5.0 10 4 100 RO MVK + HCHO + HO 5.0 10 4 5.0 10 4
101 RO + O MF + HCHO + HO.5 10 4.5 10 4 10 RO MF + HCHO + HO.5 10 4.5 10 4 10 R4O + O MACR + HCHO + HO 5.0 10 4 5.0 10 4 104 R4O MACR + HCHO + HO 5.0 10 4 5.0 10 4 105 R4O + O MF + HCHO + HO.5 10 4.5 10 4 106 R4O MF + HCHO + HO.5 10 4.5 10 4 107 R5O + O carbonyl + HO 1.0 10 5 1.0 10 5 108 R5O carbonyl + HO 1.0 10 5 1.0 10 5 109 R6O + O MACR + HCHO + HO 1.0 10 5 1.0 10 5 110 R6O MACR + HCHO + HO 1.0 10 5 1.0 10 5 111 11 11 CH O + O HO + HCHO 1.0 10 5 1.0 10 5 R1O + CHO R1O + CHO + O 6.0 10 7 6.0 10 7 R1O + CHO alcohol+ C5 carbonyl+ HCHO+ O 6.0 10 7 6.0 10 7
114 115 116 117 118 119 10 11 1 1 14 15 RO + CHO RO + CHO + O 6.0 10 7 6.0 10 7 RO + CHO alcohol+ C5 carbonyl+ HCHO+ O 6.0 10 7 6.0 10 7 RO + CHO RO + CHO + O 6.0 10 7 6.0 10 7 RO + CHO alcohol+ C5 carbonyl+ HCHO+ O 6.0 10 7 6.0 10 7 R4O + CHO R4O + CHO + O 6.0 10 7 6.0 10 7 R4O + CHO alcohol+ C5 carbonyl+ HCHO+ O 6.0 10 7 6.0 10 7 R5O + CHO R5O + CHO + O 6.0 10 7 6.0 10 7 R5O + CHO alcohol+ C5 carbonyl+ HCHO+ O 6.0 10 7 6.0 10 7 R6O + CHO R6O + CHO + O 6.0 10 7 6.0 10 7 R6O + CHO alcohol+ C5 carbonyl+ HCHO+ O 6.0 10 7 6.0 10 7 CH O + CHO CHO + CHO + O 7. 10 5 7. 10 5 CH O + CHO alcohol+ C5 carbonyl+ HCHO+ O 1.5 10 6 1.5 10 6 16 MACR + OH 0.5 CH (OH)C (CH )CHO + 0.5 CH C(OH)(CH )CHO 1. 10 10 1. 10 10
17 MVK + OH 0.7 CH (OH)C HC(O)CH + 0. CH CH(OH)C(O) CH 1. 10 10 1. 10 10 18 CH (OH)C (CH )CHO + O CH (OH)C(OO )(CH )CHO. 10 9. 10 9 19 CH C(OH)(CH )CHO + O OOCH C(OH)(CH )CHO 1.8 10 9 1.8 10 9 10 CH (OH)C HC(O)CH + O CH (OH)C(OO)HC(O)CH. 10 9. 10 9 11 CH CH(OH)C(O)CH + O OOCH CH(OH)C(O) CH 1.8 10 9 1.8 10 9 1 CH (OH)C(OO )(CH )CHO O CH C(O)CHO + CH OH + 0. CH (OH)C(O)CHO + 0. CH + 0.8 CH (OH)C(O)CH + 0.8 CHO + 4.0 10 7 4.0 10 7 1 OOCH C(OH)(CH )CHO OHCC(OH)(CH )CHO + H O.0 10 8.0 10 8 14 OOCH C(OH)(CH )CHO OHCC(OH)(CH )CHO + CH (OH)C(OH)(CH )CHO + O.0 10 8.0 10 8 15 OOCH C(OH)(CH)CHO HCHO + CH C (OH)CHO + O 4.0 10 7 4.0 10 7 16 CHO + O CO + OH 4.5 10 9 4.5 10 9 17 CHO HCHO + HCOOH.0 10 8.0 10 8 18 CH C (OH)CHO + O CH C(OO)(OH)CHO.0 10 9.0 10 9
19 CH C(OO )(OH)CHO 0.8 CH COOH + 0.8 CHO + 0.8 OHCCOOH + 0.8 CH + 0. CH C(O)CHO + 0. OH 1.0 10 8 1.0 10 8 140 CH (OH)C(OO )HC(O)CH CH (OH)C(O)C(O)CH + H O 1.0 10 8 1.0 10 8 141 CH (OH)C(OO )HC(O)CH CH (OH)C(O)C(O)CH + CH (OH)CH(OH)C(O)CH + O 1.0 10 8 1.0 10 8 14 CH 1.4 CH (OH)C(OO )HC(O)CH O (OH)CHO + 1.4 CH CO + 0.6 CH OH + 0.6 CH C(O)CHO + 8.0 10 7 8.0 10 7 14 OOCH CH(OH)C(O)CH OHCCH(OH)C(O)CH + H O 1.0 10 8 1.0 10 8 144 OOCH CH(OH)C(O)CH OHCCH(OH)C(O)CH + CH (OH)CH(OH)C(O)CH + O 1.0 10 8 1.0 10 8 145 OOCH CH(OH)C(O)CH HCHO + CH C(O)C H(OH) + O 8.0 10 7 8.0 10 7 146 CH CO + O CH CO 5.0 10 9 5.0 10 9 147 CH CO O + CO + CH 1.0 10 7 1.0 10 7 148 CH CO + OH CH COOH 1.0 10 9 1.0 10 9 149 CH CO CH COCOCH 1.0 10 9 1.0 10 9 150 CH CO + CH O O + HCHO + CH COOH 1.7 10 8 1.7 10 8
151 CH (OH)CHO + OH CH (OH)COOH + HO + H O 5.0 10 8 5.0 10 8 15 CH (OH)COOH+ OH CH(OH)COOH+ H O 5.4 10 8 5.4 10 8 15 CH(OH)COOH+ O OOCH(OH)COOH.0 10 9.0 10 9 154 OOCH(OH)CO OH + H O CH(OH) COOH + HO 5 5 155 CH(OH) COOH + OH HOOCCOOH + HO + H O.6 10 8.6 10 8 156 CH (OH)CHO + OH (OH) CHCH(OH) + HO 1.0 10 9 1.0 10 9 157 CH(OH) COOH + HO HCOOH+ CO + HO 0. 0. 158 (OH) CHCH(OH) + OH CHOCOOH + HO 1.1 10 9 1.1 10 9 159 CH C(O)CH(OH) + O CH C(O)CH(OH) OO.0 10 9.0 10 9 160 CH C(O)CH(OH)OO CH C(O)CHO + HO.1 10.1 10 161 CH C(O)CH(OH)OO CH C(O)COOH + H O.5 10 8.5 10 8 16 CHOCOOH + OH HOOCCOOH+ HO + H O 1. 10 9 1. 10 9 16 HCHO + H O CH (OH) 0.18 (F) 5.1 10-0.18 (F) 5.1 10 -
(B) (B) 164 CH (OH) + OH H O + HO + HCOOH 1.0 10 9 1.0 10 9 - + 165 HCOOH HCOO + H 8.9 10 6 (F) 5.0 10 10 (B) 8.9 10 6 (F) 5.0 10 10 (B) 166 HCOOH + OH H O + HO + CO 1. 10 8 1. 10 8 167 - - HCOO + OH OH + HO + CO 4.0 10 9 4.0 10 9 168 CH C(O)CHO + H O CH C(O)CH(OH) 1.5 (F) 0.5 (B) 1.5 (F) 0.5 (B) 169 CH C(O)CH(OH) + OH CH C(O)C(OH) + H O 1.1 10 9 1.1 10 9 170 CH C(O)C(OH) + O CH C(O)C(OH) OO.0 10 9.0 10 9 171 CH C(O)C(OH) OO CH C(O)COOH + HO 1.0 10 7 1.0 10 7 17 17 CH C(O)COOH CH C(O)COO CH - - C(O)COO + hv CH COO - + H + 1.8 10 8 (F) 5.0 10 10 (B) 5.0 10-4 (s -1 ) 1.8 10 8 (F) 5.0 10 10 (B) 5.0 10-4 (s -1 )
174 - - CH C(O)COO + H O CH COO + H O + CO 0.11 0.11 175 CH C(O)COOH + OH CH C(O)COOH + H O 1. 10 8 1. 10 8 176 CH C(O)COOH + O O CH C(O)COOH 1.9 10 7 1.9 10 7 177 O CH C(O)COOH OHCC(O)COOH + H O.0 10 7.0 10 7 178 CH COOH CH COO - + H + 8.8 10 5 (F) 5.0 10 10 (B) 8.8 10 5 (F) 5.0 10 10 (B) 179 CH COOH + OH HOOCCOOH 1.6 10 7 1.6 10 7 180 CH COO HOOCCOO - - + OH 8.5 10 7 8.5 10 7 181 HOOCCOOH + OH CO + H O + HO 1.4 10 6 1.4 10 6 - - 18 HOOCCOO + OH CO + H O + O 4.7 10 7 4.7 10 7 - + 18 HOOCCOOH HOOCCOO + H. 10 9 (F) 5.0 10 10 (B). 10 9 (F) 5.0 10 10 (B) 184 CH + O CH 4.1 10 9 4.1 10 9 O
185 CH O + CH O CH OH + HCHO + O 1.7 10 8 1.7 10 8 186 CH OH + O OOCHOH.0 10 9.0 10 9 187 OOCH OH CH OH + HCHO + O 1.1 10 9 1.1 10 9 The formula or description of the simplified name in Table.1 are as follows: Name Formula/description Name Formula/description R1O HOCH C(CH ) = CHCH OO R5O OCH C(CH ) = CHCH OH RO HOCH C(CH )(OO )CH = CH R6O CH = C(CH )CH(O )CH OH RO R4O R5O R6O CH = CHC(CH )(OH)CH OO MACAOO CH (OH)C(OO )(CH )CHO CH = C(CH )CH(OH)CH OO MACBOO OOCH C(OH)(CH )CHO OOCH C(CH ) = CHCH OH MVKAOO CH (OH)C(OO)HC(O)CH CH = C(CH )CH(OO )CH OH MVKBOO OOCH CH(OH)C(O) CH R1O HOCH C(CH ) = CHCH O HMVK CH CH (OH)C HC(O)CH CH(OH)C(O)CH RO HOCH C(CH )(O )CH = CH C5H 8O Carbonyls (internal double bond)
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Fig.S1. The time series of products in the aqueous isoprene-oh reaction under the condition of 1.5 L top space in the.1 L reactor.
0.6 -a- -b- -c- ln ([ISO]0/[ISO]t) 0.4 0. y = 0.75x r = 0.997 ln ([MACR]0/[MACR]t) y = 0.779x r = 0.991 ln ([MVK]0/[MVK]t) y = 0.760x r = 0.99 0.0 0 0. 0.4 0.6 0.8 0 0. 0.4 0.6 0.8 0 0. 0.4 0.6 0.8 ln ([SA] 0 /[SA] t ) ln ([SA] 0 /[SA] t ) ln ([SA] 0 /[SA] t ) Fig.S. Experiments 1 and (green and blue) for the kinetics of aqueous OH-initiated oxidation of isoprene (ISO), methacrolein (MACR), and methyl vinyl ketone (MVK) relative to salicylic acid at 8 K. (a) ISO/SA; (b) MACR/SA; (c) MVK/SA.