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| Titel |
New and extended parameterization of the thermodynamic model AIOMFAC: calculation of activity coefficients for organic-inorganic mixtures containing carboxyl, hydroxyl, carbonyl, ether, ester, alkenyl, alkyl, and aromatic functional groups |
| VerfasserIn |
A. Zuend, C. Marcolli, A. M. Booth, D. M. Lienhard, V. Soonsin, U. K. Krieger, D. O. Topping, G. McFiggans, T. Peter, J. H. Seinfeld |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 11, no. 17 ; Nr. 11, no. 17 (2011-09-07), S.9155-9206 |
| Datensatznummer |
250010057
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| Publikation (Nr.) |
 copernicus.org/acp-11-9155-2011.pdf |
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| Zusammenfassung |
| We present a new and considerably extended
parameterization of the thermodynamic activity coefficient model AIOMFAC
(Aerosol Inorganic-Organic Mixtures Functional groups Activity Coefficients)
at room temperature. AIOMFAC combines a Pitzer-like electrolyte solution
model with a UNIFAC-based group-contribution approach and explicitly accounts
for interactions between organic functional groups and inorganic ions. Such
interactions constitute the salt-effect, may cause liquid-liquid phase
separation, and affect the gas-particle partitioning of aerosols. The
previous AIOMFAC version was parameterized for alkyl and hydroxyl functional
groups of alcohols and polyols. With the goal to describe a wide variety of
organic compounds found in atmospheric aerosols, we extend here the
parameterization of AIOMFAC to include the functional groups carboxyl,
hydroxyl, ketone, aldehyde, ether, ester, alkenyl, alkyl, aromatic
carbon-alcohol, and aromatic hydrocarbon. Thermodynamic equilibrium data of
organic-inorganic systems from the literature are critically assessed and
complemented with new measurements to establish a comprehensive database. The
database is used to determine simultaneously the AIOMFAC parameters
describing interactions of organic functional groups with the ions
H+, Li+, Na+, K+, NH4+,
Mg2+, Ca2+, Cl−, Br−, NO3−,
HSO4−, and SO42−. Detailed descriptions of different
types of thermodynamic data, such as vapor-liquid, solid-liquid, and
liquid-liquid equilibria, and their use for the model parameterization are
provided. Issues regarding deficiencies of the database, types and
uncertainties of experimental data, and limitations of the model, are
discussed. The challenging parameter optimization problem is solved with a
novel combination of powerful global minimization algorithms. A number of
exemplary calculations for systems containing atmospherically relevant
aerosol components are shown. Amongst others, we discuss aqueous mixtures of
ammonium sulfate with dicarboxylic acids and with levoglucosan. Overall, the
new parameterization of AIOMFAC agrees well with a large number of
experimental datasets. However, due to various reasons, for certain mixtures
important deviations can occur. The new parameterization makes AIOMFAC a
versatile thermodynamic tool. It enables the calculation of activity
coefficients of thousands of different organic compounds in organic-inorganic
mixtures of numerous components. Models based on AIOMFAC can be used to
compute deliquescence relative humidities, liquid-liquid phase separations,
and gas-particle partitioning of multicomponent mixtures of relevance for
atmospheric chemistry or in other scientific fields. |
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