Computation of liquid-liquid equilibria and phase stabilities: Implications for RH-dependent gas/particle partitioning of organic-inorganic aerosols
| LEADER | naa a22 4500 | ||
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| 001 | 528787306 | ||
| 005 | 20180924065503.0 | ||
| 007 | cr unu---uuuuu | ||
| 008 | 180924s2010 xx s 000 0 eng | ||
| 024 | 7 | 0 | |a 10.3929/ethz-b-000022283 |2 doi |
| 024 | 7 | 0 | |a 10.5194/acp-10-7795-2010 |2 doi |
| 035 | |a (ETHRESEARCH)oai:www.research-collecti.ethz.ch:20.500.11850/22283 | ||
| 245 | 0 | 0 | |a Computation of liquid-liquid equilibria and phase stabilities: Implications for RH-dependent gas/particle partitioning of organic-inorganic aerosols |h [Elektronische Daten] |c [Andreas Zuend, Claudia Marcolli, Thomas Peter, John H. Seinfeld] |
| 246 | 0 | |a Atmos. chem. phys. | |
| 506 | |a Open access |2 ethresearch | ||
| 520 | 3 | |a Semivolatile organic and inorganic aerosol species partition between the gas and aerosol particle phases to maintain thermodynamic equilibrium. Liquid-liquid phase separation into an organic-rich and an aqueous electrolyte phase can occur in the aerosol as a result of the salting-out effect. Such liquid-liquid equilibria (LLE) affect the gas/particle partitioning of the different semivolatile compounds and might significantly alter both particle mass and composition as compared to a one-phase particle. We present a new liquid-liquid equilibrium and gas/particle partitioning model, using as a basis the group-contribution model AIOMFAC (Zuend et al., 2008). This model allows the reliable computation of the liquid-liquid coexistence curve (binodal), corresponding tie-lines, the limit of stability/metastability (spinodal), and further thermodynamic properties of multicomponent systems. Calculations for ternary and multicomponent alcohol/polyol-water-salt mixtures suggest that LLE are a prevalent feature of organic-inorganic aerosol systems. A six-component polyol-water-ammonium sulphate system is used to simulate effects of relative humidity (RH) and the presence of liquid-liquid phase separation on the gas/particle partitioning. RH, salt concentration, and hydrophilicity (water-solubility) are identified as key features in defining the region of a miscibility gap and govern the extent to which compound partitioning is affected by changes in RH. The model predicts that liquid-liquid phase separation can lead to either an increase or decrease in total particulate mass, depending on the overall composition of a system and the particle water content, which is related to the hydrophilicity of the different organic and inorganic compounds. Neglecting non-ideality and liquid-liquid phase separations by assuming an ideal mixture leads to an overestimation of the total particulate mass by up to 30% for the composition and RH range considered in the six-component system simulation. For simplified partitioning parametrizations, we suggest a modified definition of the effective saturation concentration, Cj*, by including water and other inorganics in the absorbing phase. Such a Cj* definition reduces the RH-dependency of the gas/particle partitioning of semivolatile organics in organic-inorganic aerosols by an order of magnitude as compared to the currently accepted definition, which considers the organic species only. | |
| 540 | |a Creative Commons Attribution 3.0 Unported |u http://creativecommons.org/licenses/by/3.0 |2 ethresearch | ||
| 700 | 1 | |a Zuend |D Andreas |e joint author | |
| 700 | 1 | |a Marcolli |D Claudia |e joint author | |
| 700 | 1 | |a Peter |D Thomas |e joint author | |
| 700 | 1 | |a Seinfeld |D John H. |e joint author | |
| 773 | 0 | |t Atmospheric Chemistry and Physics |d Munich : European Geophysical Society |g 10 (16), pp. 7795-7820 |x 1680-7375 | |
| 856 | 4 | 0 | |u http://hdl.handle.net/20.500.11850/22283 |q text/html |z WWW-Backlink auf das Repository (Open access) |
| 908 | |D 1 |a Journal Article |2 ethresearch | ||
| 950 | |B ETHRESEARCH |P 856 |E 40 |u http://hdl.handle.net/20.500.11850/22283 |q text/html |z WWW-Backlink auf das Repository (Open access) | ||
| 950 | |B ETHRESEARCH |P 700 |E 1- |a Zuend |D Andreas |e joint author | ||
| 950 | |B ETHRESEARCH |P 700 |E 1- |a Marcolli |D Claudia |e joint author | ||
| 950 | |B ETHRESEARCH |P 700 |E 1- |a Peter |D Thomas |e joint author | ||
| 950 | |B ETHRESEARCH |P 700 |E 1- |a Seinfeld |D John H. |e joint author | ||
| 950 | |B ETHRESEARCH |P 773 |E 0- |t Atmospheric Chemistry and Physics |d Munich : European Geophysical Society |g 10 (16), pp. 7795-7820 |x 1680-7375 | ||
| 898 | |a BK010053 |b XK010053 |c XK010000 | ||
| 949 | |B ETHRESEARCH |F ETHRESEARCH |b ETHRESEARCH |j Journal Article |c Open access | ||