Title: | Unified Theory of Vapor-Wall Mass Transport in Teflon-Walled Environmental Chambers |
Author(s): | Huang Y; Zhao R; Charan SM; Kenseth CM; Zhang X; Seinfeld JH; |
Address: | "Division of Geological and Planetary Sciences, California Institute of Technology , Pasadena, California 91125, United States. Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States. National Center for Atmospheric Research , Boulder, Colorado 80301, United States. Division of Engineering and Applied Science, California Institute of Technology , Pasadena, California 91125, United States" |
ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Linking) |
Abstract: | "Secondary organic aerosol (SOA) formation is studied in laboratory chambers, in which volatile organic compounds (VOCs) are oxidized to produce low-volatility compounds that condense into the aerosol phase. It has been established that such oxidized low-volatility compounds can partition into the chamber walls, which traditionally consist of Teflon film. Several studies exist in which the rates of uptake of individual vapor compounds to the chamber walls have been measured, but a unified theory capable of describing the range of experimental measurements has been lacking. Here, a two-layer model of observed short and long vapor-wall interaction time scales in Teflon-walled environmental chambers is presented and shown to be consistent with experimental data on the rate of wall deposition of more than 90 compounds. Semiempirical relationships between key parameters in the model and vapor molecular properties are derived, which can be used to predict the fate of gas-phase vapor in the chamber under dry conditions" |
Keywords: | Aerosols *Air Pollutants Gases Polytetrafluoroethylene Volatilization; |
Notes: | "MedlineHuang, Yuanlong Zhao, Ran Charan, Sophia M Kenseth, Christopher M Zhang, Xuan Seinfeld, John H eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2018/01/30 Environ Sci Technol. 2018 Feb 20; 52(4):2134-2142. doi: 10.1021/acs.est.7b05575. Epub 2018 Feb 9" |