Predictions of homogeneous nucleation rates for n-alkanes accounting for the diffuse phase interface and capillary waves

0481360 - ÚT 2018 RIV US eng J - Journal Article
Planková, Barbora - Vinš, Václav - Hrubý, Jan
Predictions of homogeneous nucleation rates for n-alkanes accounting for the diffuse phase interface and capillary waves.
Journal of Chemical Physics. Roč. 147, č. 16 (2017), č. článku 164702. ISSN 0021-9606. E-ISSN 1089-7690
R&D Projects: GA MŠMT(CZ) 7F14466; GA ČR(CZ) GJ15-07129Y
Institutional support: RVO:61388998
Keywords : nucleation * classical nucleation theory * density gradient theory
OECD category: Thermodynamics
Impact factor: 2.843, year: 2017

Density gradient theory (DGT) and capillary waves (CWs) are used to predict size-dependent surface tensions and nucleation rates for selected n-alkanes. The DGT model was completed by PC-SAFT equation of state (EoS) and compared to the classical nucleation theory and the Peng–Robinson EoS. The critical clusters are practically free of CWs because they are so small that even the smallest wavelengths of CWs do not fit into their finite dimensions. A correction for the effect of CWs on the surface tension is presented. Of the effects investigated, the most pronounced is the suppression of CWs which causes a sizable decrease of the predicted nucleation rates. The major difference between experimental nucleation rate data and theoretical predictions remains in the temperature dependence. For normal alkanes, this discrepancy is much stronger than observed, e.g., for water. Theoretical corrections developed here have a minor influence on the temperature dependence.
Permanent Link: http://hdl.handle.net/11104/0278069