Details
| Original language | English |
|---|---|
| Pages (from-to) | 850-859 |
| Number of pages | 10 |
| Journal | Journal of Chemical and Engineering Data |
| Volume | 59 |
| Issue number | 3 |
| Publication status | Published - 19 Feb 2014 |
Abstract
Different poly(ethylene glycol) (PEG) + potassium phosphate or sodium citrate aqueous two-phase systems (ATPS) were investigated at 23 C, containing different PEG types (molecular weights 2000 g·mol-1 to 8000 g·mol-1) and pH values (5 to 9). Furthermore, the effect of the added salt NaCl (0 wt % to 8 wt %) on the PEG + potassium phosphate/sodium citrate ATPS was studied at 23 C. The experimental binodal data were successfully correlated with the empirical nonlinear equation proposed by Hu. The effects of increasing molecular weight of PEG, pH, NaCl, and salt type on the obtained binodal curves were determined, resulting in a binodal curve shift toward the origin. Thus, an expansion of the two-phase region occurred by increasing molecular weight of the PEG, pH, and NaCl and due to the Gibbs free energy of hydration of ions of phosphate. Furthermore, the phase equilibrium compositions, tie-line lengths, slopes of tie-lines, critical points, and effective excluded volumes were obtained for all studied systems. Finally, the experimental tie-line compositions were successfully correlated by using the Othmer-Tobias and Bancroft equations, and linear dependency was confirmed.
ASJC Scopus subject areas
- Chemistry(all)
- General Chemistry
- Chemical Engineering(all)
- General Chemical Engineering
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In: Journal of Chemical and Engineering Data, Vol. 59, No. 3, 19.02.2014, p. 850-859.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - Influence of Different Phase-Forming Parameters on the Phase Diagram of Several PEG−Salt Aqueous Two-Phase Systems
AU - Glyk, Anna
AU - Scheper, Thomas
AU - Beutel, Sascha
PY - 2014/2/19
Y1 - 2014/2/19
N2 - Different poly(ethylene glycol) (PEG) + potassium phosphate or sodium citrate aqueous two-phase systems (ATPS) were investigated at 23 C, containing different PEG types (molecular weights 2000 g·mol-1 to 8000 g·mol-1) and pH values (5 to 9). Furthermore, the effect of the added salt NaCl (0 wt % to 8 wt %) on the PEG + potassium phosphate/sodium citrate ATPS was studied at 23 C. The experimental binodal data were successfully correlated with the empirical nonlinear equation proposed by Hu. The effects of increasing molecular weight of PEG, pH, NaCl, and salt type on the obtained binodal curves were determined, resulting in a binodal curve shift toward the origin. Thus, an expansion of the two-phase region occurred by increasing molecular weight of the PEG, pH, and NaCl and due to the Gibbs free energy of hydration of ions of phosphate. Furthermore, the phase equilibrium compositions, tie-line lengths, slopes of tie-lines, critical points, and effective excluded volumes were obtained for all studied systems. Finally, the experimental tie-line compositions were successfully correlated by using the Othmer-Tobias and Bancroft equations, and linear dependency was confirmed.
AB - Different poly(ethylene glycol) (PEG) + potassium phosphate or sodium citrate aqueous two-phase systems (ATPS) were investigated at 23 C, containing different PEG types (molecular weights 2000 g·mol-1 to 8000 g·mol-1) and pH values (5 to 9). Furthermore, the effect of the added salt NaCl (0 wt % to 8 wt %) on the PEG + potassium phosphate/sodium citrate ATPS was studied at 23 C. The experimental binodal data were successfully correlated with the empirical nonlinear equation proposed by Hu. The effects of increasing molecular weight of PEG, pH, NaCl, and salt type on the obtained binodal curves were determined, resulting in a binodal curve shift toward the origin. Thus, an expansion of the two-phase region occurred by increasing molecular weight of the PEG, pH, and NaCl and due to the Gibbs free energy of hydration of ions of phosphate. Furthermore, the phase equilibrium compositions, tie-line lengths, slopes of tie-lines, critical points, and effective excluded volumes were obtained for all studied systems. Finally, the experimental tie-line compositions were successfully correlated by using the Othmer-Tobias and Bancroft equations, and linear dependency was confirmed.
UR - http://www.scopus.com/inward/record.url?scp=84896367267&partnerID=8YFLogxK
U2 - 10.1021/je401002w
DO - 10.1021/je401002w
M3 - Article
AN - SCOPUS:84896367267
VL - 59
SP - 850
EP - 859
JO - Journal of Chemical and Engineering Data
JF - Journal of Chemical and Engineering Data
SN - 0021-9568
IS - 3
ER -