The potential contribution of organic salts to new particle growth
The potential contribution of organic salts to new particle growth
复制标题
DOI：
10.5194/acp-9-2949-2009
复制
发表时间：
2009-01-01
影响因子：
6.3
通讯作者：
Smith, J. N.
中科院分区：
文献类型：
--
作者：
Barsanti, K. C.;McMurry, P. H.;Smith, J. N.
现场和实验室测量表明，低分子量（MW）的有机酸和碱存在于积累和成核模式的颗粒，尽管它们的纯液体蒸气压相对较高。这些化合物促进现有气溶胶颗粒和新形成颗粒的质量增长的机制尚未得到彻底研究。低分子量化合物可能有助于新颗粒生长的一种机制是通过有机盐的形成。在本文中，我们使用热力学模型来探索潜在的有机盐形成大气相关的有机酸和碱的两种系统类型：一种是氨与胺在形成有机盐的相对贡献进行了评估，另一种是在有机酸和碱的挥发性降低，由于有机盐的形成进行了评估。所采用的建模方法在很大程度上依赖于基团贡献和其他必要的物理和化学参数的估计方法。这项工作的结果表明，胺可能是一个重要的贡献者有机盐的形成，实验数据是非常需要的，以提高我们的理解有机盐形成在大气相关系统，并准确地预测这种盐的潜在贡献新的颗粒生长。
Field and lab measurements suggest that low-molecular weight (MW) organic acids and bases exist in accumulation and nucleation mode particles, despite their relatively high pure-liquid vapor pressures. The mechanism(s) by which such compounds contribute to the mass growth of existing aerosol particles and newly formed particles has not been thoroughly explored. One mechanism by which low-MW compounds may contribute to new particle growth is through the formation of organic salts. In this paper we use thermodynamic modeling to explore the potential for organic salt formation by atmospherically relevant organic acids and bases for two system types: one in which the relative contribution of ammonia vs. amines in forming organic salts was evaluated, the other in which the decrease in volatility of organic acids and bases due to organic salt formation was assessed. The modeling approach employed relied heavily on group contribution and other estimation methods for necessary physical and chemical parameters. The results of this work suggest that amines may be an important contributor to organic salt formation, and that experimental data are greatly needed to improve our understanding of organic salt formation in atmospherically relevant systems and to accurately predict the potential contribution of such salts to new particle growth.