AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Modeling the Surface Tension of Complex Organic-Inorganic Solutions
Allison Schwier, Giuliana Viglione, V. FAYE MCNEILL, Columbia University
Abstract Number: 752 Working Group: Aerosols, Clouds, and Climate
Abstract Organic material is ubiquitously found in atmospheric aerosols, and a large fraction of it can be surface-active species, residing primarily at the gas-aerosol interface. These organics can form an interfacial film as well as depress surface tension, affecting trace gas uptake and cloud condensation nuclei ability, respectively. It is important to be able to predict the surface tension of atmospherically relevant complex mixtures to better understand the effects on atmospheric aerosols and their properties.
Currently, existing surface tension models have described complex systems in very dilute salt solutions or purely in water; however, these models should take into account aerosol environments (high ionic content) as well as be able to describe reactive systems. In this work, we present varying complex organic-inorganic solutions of amino acids, carboxylic acids and alpha-dicarbonyls in ammonium sulfate. We show that using an additive Szyszkowski-Langmuir equation and incorporating salt parameters reproduces most experimental data well, including reactive systems. We also discuss methods of incorporating salt effects, such as salt-organic interactions and "salting out".