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Nucleation Rates Of Ethanol And Methanol Using SAFT And PC-SAFT EOSs. Fawaz Hrahsheh Advisor ::Dr. Abdalla Obeidat Co-advisor ::Dr. H. Al-Ghanim Department of Physics JUST. Outline. ● Metastability and nucleation ● Work of formation and versions
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Nucleation Rates Of Ethanol And Methanol Using SAFT And PC-SAFT EOSs Fawaz Hrahsheh Advisor ::Dr. Abdalla Obeidat Co-advisor ::Dr. H. Al-Ghanim Department of Physics JUST
Outline ●Metastability and nucleation ● Work of formation and versions ● Temperature and saturation dependence of classical theories ● Conclusions
Metastable and unstable regions for the van der Waals fluid • The binodal curve (solid dome)separates one-phase and two-phase states • TC = critical temperature • The spinodal curve (dashed dome) separates metastable and unstable states • One true horizontal isotherm is shown
Schematic pressure – temperature phase diagram for a pure substance SPINODAL LINE • Solid black lines represent points of equilibrium two-phase coexistence • c is the critical point • b is the triple point • When, say, gas is forced to cross lines ab or bc it is no longer the thermodynamically stable phase. • The transition to the new stable phase is not instantaneous.
Kinds & Definition Of Nucleation -Homogeneous Nucleation -Hetrogeneous Nucleation • The process of formation of the critical size • cluster (droplet) which has the ability to • grow spontaneously.
The work of formation -The work of Formation is the work which is needed To form the critical size droplet • The work of formation consists from • two terms: the bulk (volumetric) term • and the surface term.
Three versions of classical theory ●Gibbs’s exact formula: ● version 1: use bulk surface tension for ● Version 2: liquid droplet is incompressible, • and ● Version 3: the vapor is an ideal gas • and • S =Pv /Pve (Supersaturation Ratio)
SAFT & PC-SAFT Theories ●SAFT…Statistical Associating Fluid Theory ● PC-SAFT….Perturbed-Chain Statistical Associating Fluid Theory
SAFT and PC-SAFT EOS ●A is the reduced free helmholtz energy ●The association term is just for polar fluids
Binodal points of ethanol And methanol using SAFT and PC-SAFT
Gibbs’s formula improves classical nucleation rates for METHANOL based on SAFT EOS.
Gibbs’s formula improves classical nucleation rates for ETHANOL based on PC-SAFT EOS.
Conclusions • P-form improves the T and S dependence for methanol and ethanol at high temperature.. • Quantitatively, P-form improves the results by than S-form for methanol and ethanol.