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ILs + H2O + K3PO4 Ternary Systems
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The TLs representation is shown in Figure 23 for the ternary system [C4mim][Cl] + K3PO4
+ water as an example measured in this work. For shorter TLLs, the TLs are approximately
parallel while for longer TLLs the tie-lines slopes start to deviate. These deviations in the
TLs slopes are in agreement with literature 84 and are related with the fact that the K3PO4-
rich phase is increasingly free of IL at longer TLLs.
[IL] / (mol.kg -1 )
6.0
5.0
4.0
3.0
2.0
1.0
Monophasic
Region
Biphasic
Region
0.0
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5
[K 3PO 4] / (mol.kg -1 )
Figure 23. Phase diagram for the [C4mim][Cl] + K3PO4 + water ternary system at 298 K: ■,
binodal curve data; ♦, TL data.
4.3.2. Partitioning of L-tryptophan in ABS
Amino acids are the constituents of proteins. The partitioning studies of such biomolecules
in ABS have great significance, not only regarding their purification, but also with the aim
of extending them to proteins and enzymes. The success of the extractive potential of ABS
depends on the ability to manipulate phase properties to obtain the appropriate partition
coefficients and selectivity for the biomolecule of interest. There are several approaches to
manipulate a particular solute partitioning: (i) adjust the system by applying different salts
and/or ILs controlling thus the solute’ affinity; (ii) change the system composition by
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