Vapor pressures and vaporization enthalpy of (−) α-bisabolol and (dl) menthol by correlation gas chromatography
| Autor: | Harold H. Harris, Leasa Keating, James S. Chickos |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Chromatography
Vapor pressure Enthalpy Analytical chemistry 02 engineering and technology 010402 general chemistry 01 natural sciences Atomic and Molecular Physics and Optics 0104 chemical sciences Boiling point chemistry.chemical_compound 020401 chemical engineering chemistry Boiling Vaporization General Materials Science Gas chromatography 0204 chemical engineering Physical and Theoretical Chemistry Menthol Bisabolol |
| Zdroj: | The Journal of Chemical Thermodynamics. 107:18-25 |
| ISSN: | 0021-9614 |
| DOI: | 10.1016/j.jct.2016.11.027 |
| Popis: | The vapor pressures and vaporization enthalpies of (−) α-bisabolol and (dl)-menthol, two GRAS chemicals (generally recognized as safe) are evaluated by correlation gas chromatography using a series of saturated primary alcohols as standards. Vaporization enthalpies of (96.6 ± 2.4) and (74.2 ± 2.8) kJ mol−1 and vapor pressures of p/Pa = (0.020 ± 0.003) and (4.5 ± 0.44) were evaluated at T = 298.15 K for (−) α-bisabolol and (dl)-menthol, respectively, and compared to literature values. The vapor pressures of both compounds from T = (298.15 to 500) K have been derived from correlations using vapor pressures of a series of 1-alkanols and corresponding gas chromatographic retention times at 10 K intervals. The results were fit to a second order polynomial. Calculated normal boiling temperatures of TB = (574.8 and 492.7) K are calculated for (−) α-bisabolol and (dl)-menthol, respectively. A normal boiling temperature of TB = (485.2, and 489.7) K has previously been reported for (dl)-menthol. Vapor pressures for both (l)-menthol and (dl)-menthol from a previous study and (dl)-menthol from this study are compared with literature values. |
| Databáze: | OpenAIRE |
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