Liquid−Liquid Equilibria of an Aqueous Two-Phase System Formed by a Triblock Copolymer and Sodium Salts at Different Temperatures

Abstract

Phase diagrams of aqueous two-phase systems composed of a triblock copolymer (L35) 1900 g • mol -1 , sodium tartarate, sodium citrate, or sodium nitrate were determined at (283.15, 298.15, and 313.15) K. The temperature effect on the position of the binodal curves was not relevant, indicating a small enthalpic contribution associating to the phase segregation. The ability of three salts to induce the formation of the biphasic system with L35 followed the order sodium citrate > sodium tartarate > sodium nitrate. The preference of a salt-inducing phase segregation follows the Hofmeister series.

(Liquid+liquid) equilibrium of (NaNO3+PEG 4000+H2O) ternary system at different temperatures

“…Figure 1 shows that when temperature increased from 288.15 to 298.15 and after to 308.15 K, the binodal curves are moved to the closest section to the chart axes, increasing the biphasic area, however, contrary to what happens in many water/PEG/inorganic salt ATP systems, the nitrate concentration in the top liquid phase is rather high. A similar behavior for triblock copolymer (L35) + sodium nitrate + water system has been observed [37]. Figure 1 shows that the sodium nitrate increases its capacity to induce the phase separation as temperature increases.…”

Separation of phenyl acetic acid and 6-aminopenicillanic acid applying aqueous two-phase systems based on copolymers and salts

“…The results show that two-phase region expands by increasing the temperature ( Figure S3). The (16) 24,25 . The obtained binodal curves in this work are in good agreement with reported binodal curves.…”

“…At higher temperature lower amount of copolymer is needed to form two-phase system. Binodal curves of ATPSs composed of Pluronic L35 and / / at 283.15 and 298.15 K were determined through the characterization of top and bottom phases 24 , 25 . The obtained binodal curves in this work are in good agreement with reported binodal curves.…”

Monosegmented Flow Analysis Exploiting Aqueous Two-phase Systems for the Determination of Cobalt

“…10,11 A convenient approach to address the limitations of FA-SE is to perform the selective extraction of a metallic ion by using monosegmented flow analysis in conjunction with an aqueous two-phase system (ATPS), which makes determination of the analyte possible. 12 Under specific thermodynamic conditions, an ATPS can be formed by mixing aqueous solutions of (i) certain electrolytes and a polymer, 13,14 (ii) two types of watersoluble polymers 15 or (iii) two types of electrolytes. 16 The resulting systems give two immiscible liquid phases where the layers are enriched with polymers or electrolytes.…”