Influence of the aromatic ring substituents on phase equilibria of vanillins in binary systems with CO2

被引：39

作者：

Skerget, M ^{[1
]}

Cretnik, L ^{[1
]}

Knez, Z ^{[1
]}

Skrinjar, M ^{[1
]}

机构：

[1] Univ Maribor, Fac Chem & Chem Engn, SI-2000 Maribor, Slovenia

来源：

FLUID PHASE EQUILIBRIA | 2005年 / 231卷 / 01期

关键词：

solid-fluid equilibria; data; vanillin isomers; CO2; ring substituents;

D O I：

10.1016/j.fluid.2004.12.012

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

Solid-liquid phase transitions of vanillin, ethylvanillin, o-vanillin and o-ethylvanillin in presence of compressed CO2 were determined with the modified capillary method. Furthermore, the solubilities of the above mentioned vanillins in supercritical CO2 were measured at 313.2, 333.2 and 353.2 K and in the pressure range 8-30 MPa using a static-analytic method. The experimental equilibrium solubility data have been fitted to the Peng-Robinson equation in combination with two parameter van der Waals mixing rules and binary parameters were determined from the best fit. Results showed that the phase equilibria of vanillins in dense CO2 are influenced by the position of the hydroxyl group bound to the aromatic ring. Under the pressure of CO2 the melting point depression and also the solubility of both o-vanillins was higher than those of p-vanillins. Oppositely, the alchoxy group (methoxy or ethoxy) showed no significant influence on the solubility of vanillins. (c) 2004 Elsevier B.V. All rights reserved.

引用

页码：11 / 19

页数：9

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