abstract
Terpenes and terpenoids belong to the largest and most diverse class of natural products. Due to the increasing importance of their applications and the emerging perception of their impact on the environment, the available physico-chemical characterization is insufficient. In this work the water solubility of geraniol, linalool, DL-citro-nellol, thymol, eugenol, carvacrol and p-cymene, in the temperature range from (298.15 to 323.15) K, and at atmospheric pressure, is studied. Due to the low solubility of these compounds a novel technique was adopted for their measurements and validated using the aqueous solubility data for sparingly soluble aromatic compounds. The thermodynamic properties of solution were derived from the experimental data at infinite dilution. It is shown that the solubility of terpenes in water is an endothermic process confirming the existence of UCST phase diagrams, and only for carvacrol and eugenol is entropically driven. The experimental information is shown in a two-dimensional chemical space diagram providing indications to their probable distribution in the environment once released. (C) 2017 Elsevier B.V. All rights reserved.
keywords
LIQUID EQUILIBRIUM DATA; PARTITION-COEFFICIENTS; AQUEOUS SOLUBILITIES; MUTUAL SOLUBILITIES; ORGANIC-COMPOUNDS; VAPOR-PRESSURES; CHEMICALS; SYSTEMS; HYDROCARBONS; DERIVATIVES
subject category
Chemistry; Physics
authors
Martins, MAR; Silva, LP; Ferreira, O; Schroder, B; Coutinho, JAP; Pinho, SP
our authors
Bernd Schroder
Post-doc Fellowship
Liliana Patrocínio da Silva
Collaborator
Simão Pedro de Almeida Pinho
Collaboratoracknowledgements
This work was developed in the scope of the project CICECO - Aveiro Institute of Materials, POCI-01-0145-FEDER-007679, and Associate Laboratory LSRE-LCM, POCI-01-0145-FEDER-006984, both funded by FEDER under the PT2020 Partnership Agreement - Programa Operacional Competitividade e Internacionalizacao (POCI) - and by national funds through FCT - Fundacao para a Ciencia e a Tecnologia. M.A.R.M acknowledges FCT for her PhD grant (SFRH/BD/87084/2012).