Univ. Bordeaux, EPOC, UMR 5805 , F-33405 Talence Cedex, France.
J Phys Chem A. 2014 May 22;118(20):3535-40. doi: 10.1021/jp5009434. Epub 2014 May 12.
Reactions of polycyclic aromatic hydrocarbons (PAHs) with chlorine atoms may occur in specific areas such as coastal regions and the marine boundary layer. In this work, rate constants for the gas-phase reactions of naphthalene, acenaphthene, and acenaphthylene with chlorine atoms have been measured using the relative rate technique. Experiments were performed at room temperature (293 ± 2 K) and atmospheric pressure in an atmospheric simulation chamber using a proton-transfer reaction mass spectrometer (PTR-MS) to monitor the concentrations of PAHs and the reference compounds (acetone, methanol, 1,3,5-trimethylbenzene, and isoprene) as a function of time. The rate constants obtained in this work were (in units of cm(3) molecule(-1) s(-1)) (4.22 ± 0.46) × 10(-12), (3.01 ± 0.82) × 10(-10), and (4.69 ± 0.82) × 10(-10) for naphthalene, acenaphthene, and acenaphthylene, respectively. These are the first measurements of the rate constants for gas-phase reactions of Cl atoms with acenaphthene and acenaphthylene. The rate constant determined in this study for the reaction of naphthalene with Cl atoms is not in agreement with the only other previously reported value in the literature. The results are used to assess the potential role of chlorine atom reactions in the atmospheric oxidation of PAHs.
多环芳烃（PAHs）与氯原子的反应可能发生在特定区域，如沿海地区和海洋边界层。在这项工作中，使用相对速率技术测量了萘、苊和苊烯与氯原子的气相反应速率常数。实验在室温（293 ± 2 K）和大气压力下，在大气模拟室中使用质子转移反应质谱仪（PTR-MS）进行，以监测 PAHs 和参考化合物（丙酮、甲醇、1,3,5-三甲苯和异戊二烯）的浓度随时间的变化。本工作得到的速率常数（单位为 cm(3) molecule(-1) s(-1))分别为（4.22 ± 0.46）×10(-12)、（3.01 ± 0.82）×10(-10)和（4.69 ± 0.82）×10(-10)，分别对应萘、苊和苊烯。这是首次测量氯原子与苊和苊烯气相反应的速率常数。本研究中确定的萘与 Cl 原子反应的速率常数与文献中唯一另一个先前报道的值不一致。结果用于评估氯原子反应在大气中 PAHs 氧化中的潜在作用。
