title: Solubility and thermodynamic function of vanillin in ten different environmentally benign solvents.
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.
authors.affiliation: Research Center, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; Department of Pharmaceutics, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia. Electronic address: faiyazs@fastmail.fm.
authors.forename: Faiyaz
authors.initials: F
authors.lastname: Shakeel
authors.affiliation: Research Center, College of Science, King Saud University, Riyadh 11451, Saudi Arabia; Department of Pharmaceutics, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.
authors.forename: Nazrul
authors.initials: N
authors.lastname: Haq
authors.affiliation: Department of Pharmacognosy, College of Pharmacy, King Saud University, P.O. Box 2457, Riyadh 11451, Saudi Arabia.
authors.forename: Nasir A
authors.initials: NA
authors.lastname: Siddiqui
mesh_terms: D001547:Benzaldehydes / Q000737:chemistry*; D012995:Solubility; D012997:Solvents / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D001547:Benzaldehydes; D012997:Solvents; C100058:vanillin
keywords: Apelblat model; Environmentally benign solvent; Solubility; Thermodynamics; Vanillin; Van’t Hoff model