Vapor-Liquid Phase Equilibrium for Separation of Isopropanol from Its Aqueous Solution by Choline Chloride-Based Deep Eutectic Solvent Selected by COSMO-SAC Model
To separate isopropanol from its aqueous solution by distillation, the deep eutectic solvents (DESs) with choline chloride were applied to eliminate the azeotropic point, which were screened using the COSMO-SAC model. The charge density distribution over the molecular surface was calculated for isopropanol, water and DESs to analyze the interactions between the different species. Based on the screening results, a DES consisted of choline chloride and triethylene glycol with molar ratio of 1:3 was selected. To validate the selected DES for the separation of isopropanol from its aqueous solution, the isobaric vapor-liquid equilibrium (VLE) data for the system of isopropanol + water + DES were measured at pressure of 101.3 kPa. According to the measured VLE data, the azeotropic point of isopropanol and water can be eliminated by the DES at concentration of 10 wt%. Meanwhile, the thermodynamic consistency of the VLE data was checked by the van Ness test. The NRTL model was employed to correlate the VLE data, and the correlated results showed agreement with the measured VLE data.
Compounds
#
Formula
Name
1
C3H8O
propan-2-ol
2
C5H14ClNO
choline chloride
3
C6H14O4
triethylene glycol
4
H2O
water
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.