Solubility and thermodynamic function of vanillin in ten different environmentally benign solvents.

Solubility and thermodynamic function of vanillin in ten different environmentally benign solvents.

Food chemistry (2015-03-15)

Faiyaz Shakeel, Nazrul Haq, Nasir A Siddiqui

ABSTRACT

The solubility of vanillin in ten different environmentally benign solvents namely water, ethanol, ethylene glycol (EG), ethyl acetate (EA), isopropanol (IPA), propylene glycol (PG), polyethylene glycol-400 (PEG-400), Transcutol, butanol-1 and butanol-2 was measured and correlated at T=(298-318)K. The resulting experimental data were correlated with the modified Apelblat and Van't Hoff models. Both the models showed good correlation of experimental solubility data with calculated ones with root mean square deviations in the range of (0.08-1.55)%. The mole fraction solubility of vanillin was observed highest in PEG-400 (4.29 × 10(-1) at 298 K) followed by Transcutol, EA, butanol-2, ethanol, EG, PG, IPA, butanol-1 and water from T=(298-318)K. The results of thermodynamic function in terms of dissolution enthalpy, Gibbs energy and dissolution entropy showed endothermic, spontaneous and entropy-driven dissolution of vanillin in all environmentally benign solvents.

MATERIALS

Product Number

Brand

Product Description

82281

Sigma-Aldrich

1,2-Propanediol, tested according to Ph. Eur.

02891

Sigma-Aldrich

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16033

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12279

Supelco

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398039

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82280

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29221

Sigma-Aldrich

Ethanol, tested according to Ph. Eur.

02890

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Ethanol, purum, fine spirit, denaturated with 2% 2-butanone, F25 MEK¹, ~96% (based on denaturant-free substance)

02851

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45983

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439134

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271004

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360457

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E7023

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02483

Supelco

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Sigma-Aldrich

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Ethanol, BioUltra, for molecular biology, ≥99.8%, (absolute alcohol, without additive, A15 o¹)

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