Abstract

MARTINEZ, Fleming; JOUYBAN, Abolghasem  and  ACREE, William E. Some numerical analyses on the solubility of vanillin in Carbitol® + water solvent mixtures. Rev.Colomb.Quim. [online]. 2015, vol.44, n.2, pp.34-39. ISSN 0120-2804.  https://doi.org/10.15446/rev.colomb.quim.v44n2.55218.

In this communication some reported solubility values of vanillin (component 3) in 2-(2-ethoxyethoxy)ethanol (Carbitol®, component 1) + water (component 2) mixtures at five temperatures from 298.15 to 318.15 K were correlated with the Jouyban-Acree model combined with van't Hoff or Apelblat equations, obtaining models in second degree regarding the mixtures compositions. Mean percentage deviations were near to 6.0%. On the other hand, by means of the inverse Kirkwood-Buff integrals it was demonstrated that vanillin is preferentially solvated by water in water-rich mixtures (with a minimum δx_1,3 value in the mixture x₁ = 0.05, i.e. -4.29 x 10^-2) but preferentially solvated by the cosolvent in mixtures with compositions 0.12 < x₁ < 1.00 (with a maximum δx_1,3 value equal to 3.61 x 10^-2 in the mixture x₁ = 0.25). It is conjectural that hydrophobic hydration plays a relevant role in the first case, whereas, in the second case, vanillin would be acting as Lewis acid with Carbitol®.

Keywords : Vanillin; Carbitol® + water mixtures; Jouyban-Acree model; preferential solvation; IKBI.

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