(L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire., Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), CONICET, Dpto., de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba., Ciudad Universitaria, 5000, Córdoba, Argentina.
LEA - Laboratorio de Estudios Atmosféricos- INQUINOA (CONICET-UNT), Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, T4000CAN, San Miguel de Tucumán, Argentina.
Chemosphere. 2022 Feb;288(Pt 2):132546. doi: 10.1016/j.chemosphere.2021.132546. Epub 2021 Oct 12.
Relative rate coefficients of the OH radical -initiated oxidation of allyl methyl sulfide (AMS, HCCHCHSCH) and allyl ethyl sulfide (AES, HCCHCHSCHCH) have been measured at atmospheric pressure of synthetic air and 298 K: k= (4.98 ± 1.42) and k= (6.88 ± 1.49) × 10 cm molecule s by means of in situ FTIR spectroscopy. In addition, the molar yields of the main reaction products of AMS with OH radicals formed in the absence and presence of nitric oxides (NO) were determined to be the following: sulfur dioxide (95 ± 12) % and (51 ± 12) % for acrolein (50 ± 9) % and (41 ± 9) %. In the reaction of AES with OH radicals, the following molar yields were obtained: for sulfur dioxide (88 ± 13) % and (56 ± 12) % for acrolein (36 ± 9) % and (41 ± 9) %. The present results suggest that the abstraction at C3 plays an important role in the oxidation mechanism as the addition to the double bond. This work represents the first study of the OH radical interaction with AMS and AES carried out under atmospheric conditions. The atmospheric implications were discussed in terms of the atmospheric residence times of the sulfur-containing compounds studied and the products formed in the presence and absence of NOx. SO formation seems to be the main fate of the gas-phase allyl sulfides oxidation with significant acidifying potentials and short-chain aldehydes production like formaldehyde and acetaldehyde.
在大气压力下和 298 K 时，通过原位 FTIR 光谱法测量了 OH 自由基引发的烯丙基甲基硫醚（AMS，HCCHCHSCH）和烯丙基乙基硫醚（AES，HCCHCHSCHCH）氧化的相对速率系数：k=（4.98±1.42）和 k=（6.88±1.49）×10 cm3 分子-1 s-1。此外，还确定了在不存在和存在氮氧化物（NO）的情况下，AMS 与 OH 自由基形成的主要反应产物的摩尔产率为：二氧化硫（95±12）%和（51±12）%的丙烯醛（50±9）%和（41±9）%。在 AES 与 OH 自由基的反应中，得到了以下摩尔产率：二氧化硫（88±13）%和（56±12）%的丙烯醛（36±9）%和（41±9）%。目前的结果表明，C3 的抽提在氧化机制中起着重要作用，就像双键的加成一样。这项工作代表了在大气条件下首次对 OH 自由基与 AMS 和 AES 相互作用的研究。根据所研究的含硫化合物在大气中的停留时间以及在存在和不存在 NOx 的情况下形成的产物，讨论了大气影响。SO 形成似乎是气相烯丙基硫醚氧化的主要归宿，具有显著的酸化潜力和短链醛如甲醛和乙醛的生成。
