当前位置: X-MOL 学术ACS Earth Space Chem. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Volatility Change during Droplet Evaporation of Pyruvic Acid
ACS Earth and Space Chemistry ( IF 2.9 ) Pub Date : 2020-04-01 , DOI: 10.1021/acsearthspacechem.0c00044
Sarah S. Petters 1 , Thomas G. Hilditch 2 , Sophie Tomaz 1 , Rachael E. H. Miles 2 , Jonathan P. Reid 2 , Barbara J. Turpin 1
Affiliation  

Atmospheric water-soluble organic gases such as pyruvic acid are produced in large quantities by photochemical oxidation of biogenic and anthropogenic emissions and undergo water-mediated reactions in aerosols and hydrometeors. These reactions can contribute to aerosol mass by forming less-volatile compounds. Although progress is being made in understanding the relevant aqueous chemistry, little is known about the chemistry that takes place during droplet evaporation. Here, we examine the evaporation of aqueous pyruvic acid droplets using both the vibrating orifice aerosol generator (VOAG) and an electrodynamic balance (EDB). In some cases, pyruvic acid was first oxidized by OH radicals. The evaporation behavior of oxidized mixtures was consistent with expectations based on known volatilities of reaction products. However, independent VOAG and EDB evaporation experiments conducted without oxidation also resulted in stable residual particles; the estimated volume yield was 10–30% of the initial pyruvic acid. Yields varied with temperature and pyruvic acid concentration across cloud-, fog-, and aerosol-relevant concentrations. The formation of low-volatility products, likely cyclic dimers, suggests that pyruvic acid accretion reactions occurring during droplet evaporation could contribute to the gas-to-particle conversion of carbonyls in the atmosphere.

中文翻译:

丙酮酸液滴蒸发过程中的挥发性变化

大气中的水溶性有机气体,例如丙酮酸,是通过生物化学和人为排放的光化学氧化产生的,并在气溶胶和水凝物中发生水介导的反应。这些反应可通过形成挥发性较小的化合物来促进气溶胶质量。尽管在了解相关的水化学方面已经取得了进展,但对液滴蒸发过程中发生的化学反应知之甚少。在这里,我们使用振动孔口气雾发生器(VOAG)和电动平衡(EDB)来检查丙酮酸水溶液的蒸发。在某些情况下,丙酮酸首先被OH自由基氧化。氧化混合物的蒸发行为与基于已知反应产物挥发性的预期一致。然而,在不进行氧化的情况下进行的独立VOAG和EDB蒸发实验也得到了稳定的残留颗粒;估计的产量为初始丙酮酸的10–30%。产量随温度,丙酮酸浓度在云,雾和气溶胶相关浓度之间变化。低挥发性产物(可能是环状二聚体)的形成表明,在液滴蒸发过程中发生的丙酮酸积聚反应可能有助于大气中羰基的气体-颗粒转化。
更新日期:2020-04-01
down
wechat
bug