| Title: | Effect of inorganic salts on the volatility of organic acids |
| Author(s): | Hakkinen SA; McNeill VF; Riipinen I; |
| Address: | "Department of Chemical Engineering, Columbia University , 500 West 120th Street, New York, New York 10027, United States" |
| ISSN/ISBN: | 1520-5851 (Electronic) 0013-936X (Print) 0013-936X (Linking) |
| Abstract: | "Particulate phase reactions between organic and inorganic compounds may significantly alter aerosol chemical properties, for example, by suppressing particle volatility. Here, chemical processing upon drying of aerosols comprised of organic (acetic, oxalic, succinic, or citric) acid/monovalent inorganic salt mixtures was assessed by measuring the evaporation of the organic acid molecules from the mixture using a novel approach combining a chemical ionization mass spectrometer coupled with a heated flow tube inlet (TPD-CIMS) with kinetic model calculations. For reference, the volatility, i.e. saturation vapor pressure and vaporization enthalpy, of the pure succinic and oxalic acids was also determined and found to be in agreement with previous literature. Comparison between the kinetic model and experimental data suggests significant particle phase processing forming low-volatility material such as organic salts. The results were similar for both ammonium sulfate and sodium chloride mixtures, and relatively more processing was observed with low initial aerosol organic molar fractions. The magnitude of low-volatility organic material formation at an atmospherically relevant pH range indicates that the observed phenomenon is not only significant in laboratory conditions but is also of direct atmospheric relevance" |
| Keywords: | "Acetic Acid/chemistry Aerosols/*chemistry Air Ionization Carboxylic Acids/*chemistry Citric Acid/chemistry Kinetics Mass Spectrometry/*methods Models, Theoretical Oxalic Acid/chemistry Salts Succinic Acid/chemistry Vapor Pressure Volatilization;" |
| Notes: | "MedlineHakkinen, Silja A K McNeill, V Faye Riipinen, Ilona eng 278277/ERC_/European Research Council/International Research Support, Non-U.S. Gov't 2014/11/05 Environ Sci Technol. 2014 Dec 2; 48(23):13718-26. doi: 10.1021/es5033103. Epub 2014 Nov 19" |
