Atmospheric reactivity of HCCCH2OH (2-propyn-1-ol) toward OH radicals: experimental determination and theoretical comparison with its alkyne analogue

The rate coefficient for the reaction of propargyl alcohol (2-propyn-1-ol,2P1OL) with OH radicals has been determined using gas chromatography with a flame ionization detector (GC/FID) at 298 K and atmospheric pressure.

Yields of carbonyl products from gas-phase reactions of fragrance compounds with OH radical and ozone

Chamber studies to quantify formation yields of oxygenated organic reaction products were performed for gas-phase reactions of the hydroxyl radical (OH*) and ozone (03) with the common cleaning product terpene compounds limonene, alpha-terpineol, and geraniol. The reaction products observed were identified and quantified using derivatization by O-(2,3,4,5,6-pentafluorobenzyl)hydroxylamine (PFBHA) and gas chromatography/mass spectrometry. Limonene rate constants and product mechanisms have been examined previously. Several of these investigations have measured productyields from limonene reactions and those results are compared with the results presented here. Although rate constants and product mechanisms have previously been investigated for alpha-terpineol and geraniol, yields of oxygenated organic reaction products have not been measured. Reactions from the fragrance compounds in this study produced several dicarbonyl reaction products such as glyoxal, methylglyoxal, and 4-oxopentanal which were observed from all three terpenes. Total carbonyl yields ranged from 5.1% for the limonene + O3 reaction to 92% for the geraniol + O3 reaction.

Gas-phase chemistry of (alpha-terpineol with ozone and OH radical: rate constants and products

A bimolecular rate constant, kOH+alpha-terpineol, of (1.9 +/- 0.5) x 10(-10) cm3 molecule(-1) s(-1) was measured using gas chromatography/mass spectrometry and the relative rate technique for the reaction of the hydroxyl radical (OH) with alpha-terpineol (1-methyl-4-isopropyl-1-cyclohexen-8-ol) at (297 +/- 3) K and 1 atm total pressure. Additionally, a bimolecular rate constant, kO3+alpha-terpineol, of (3.0 +/- 0.2) x 10(-16) cm3 molecule(-1) s(-1) was measured by monitoring the first order decrease in ozone concentration as a function of excess alpha-terpineol. To better understand alpha-terpineol's gas-phase transformation in the indoor environment, the products of the alpha-terpineol + OH and alpha-terpineol + 03 reactions were also investigated. The positively identified alpha-terpineol/OH reaction products were acetone, ethanedial (glyoxal, HC(=O)C(=O)H), and 2-oxopropanal (methyl glyoxal, CH3C(=O)C(=O)H). The positively identified alpha-terpineol/O3 reaction product was 2-oxopropanal (methyl glyoxal, CH3C(=O)C(=O)H). The use of derivatizing agents O-(2,3,4,5,6-pentalfluorobenzyl)hydroxylamine (PFBHA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) clearly indicated that several other reaction products were formed. The elucidation of these other reaction products was facilitated by mass spectrometry of the derivatized reaction products coupled with plausible alpha-terpineol/OH and alpha-terpineol/O3 reaction mechanisms based on previously published volatile organic compound/ OH and volatile organic compound/O3 gas-phase reaction mechanisms.