Phase separation in aqueous solutions of polypropylene glycol and sodium citrate: Effects of temperature and pH

Aqueous immiscibility of cholinium chloride ionic liquid and Triton surfactants

“…As expected, the deviation data justify the greater suitability of using equation (4) for the description of the binodal results when the cholinium-based ionic liquid is used as a phase splitter, no matter the temperature or surfactant used. These results are in agreement with the findings reported by Hamzehzadeh and Zaffarani [21], where a four-parameter based equation yielded lower deviations than the well-known Merchuk model. The analysis of the effect of the operation temperature reveals an increased immiscibility at higher temperatures, in agreement with previous results of our group based on the ABS behavior of imidazolium-based ionic liquids and the same non-ionic surfactants [16].…”

“…As it can be observed, the binodal curve and the SLLE phase boundary divide three clear regions: the one-liquid phase (L), the biphasic region (L + L), and the solid-two liquid phase (S + L). In order to characterize the binodal curves properly, two well-known models were proposed [20,21]:…”

The Effect of Temperature on Different Aqueous Two-Phase Diagrams of Polyethylene Glycol (PEG 6000, PEG 8000, and PEG 10000) + Potassium Sodium Tartrate + Water

“…Empirical correlations used in previous LLE studies were used to validate the reliability of the calculated LLE data of this study. The equations used in this case were the Othmer–Tobias (eq ) and Bancroft (eq ) empirical equations, , where w b and w t indicate the bottom and top weight fractions (w/w) of water (H), PEG (P), and potassium sodium tartrate (S), respectively, and k , k 1 , r and n are fit parameters. Linearization of these equations indicates that the LLE data are valid and, in most cases, produced acceptable consistency (Figure ).…”

Density, Refractive Index, pH, and Cloud Point Temperature Measurements and Thermal Expansion Coefficient Calculation for PPG400, PE62, L64, L35, PEG400, PEG600, or PEG1000 + Water Systems

“…In the literature, aqueous polymer systems were studied with PPG 400 , random and block copolymers, such as Ultraric PE62 and Pluronics L64 and L35, and PEG 400 , PEG 600 , and PEG 1000 because these compounds present advantages such as regenerability due to thermoseparation efficiency, low or controlled toxicity, nonflammability, and commercial availability …”

“…In the literature, aqueous polymer systems were studied with PPG 400 , 37 random and block copolymers, such as Ultraric PE62 38 and Pluronics L64 39 and L35, 40 and PEG 400 , 41 PEG 600 , 42 and PEG 1000 43 because these compounds present advantages such as regenerability due to thermoseparation efficiency, 38 low or controlled toxicity, 44 nonflammability, 45 and commercial availability. 46 However, regarding thermophysical properties for aqueous systems composed by these polymers, density (ρ) measurements were reported for aqueous solutions of PPG 400 , 11,47 L64, 48 PEG 400 , 49−51 PEG 600 , 47,50 and PEG 1000 , 51,52 while no such data were not found for PE62 and L35.…”