3. Results and discussion
The results of l-Gn solubility in water and mixed solvents are listed in Table 1.
Fig. 4 gives the plot of the solubility of l-Gn in these solvents at a temperature range of about 278–313 K.
In all of the tables and figures,
R, which represents the solvent molar ratio of the solvent mixture,
mole fraction,
respectively.
The subscripts (+) and () refer to cation
and anion. Equation (1) can be used not only for aqueous solutions
but also for organic or mixed solvent electrolyte solutions [19].
Furthermore, the solubility product in pure m solvent, Ksm, is a
function of temperature and can be expressed as follows:
the solubility would increase with the increasing of R,
which indicates that pure water has a high dissolving power.
Among the two different mixed solvent systems,
only if it has the same solvent molar ratio (R),
the molar fraction solubility will decrease in the same degree.