Influence of supercritical CO(2) pressurization on the phase behavior of mixed cholesteryl esters.
Evidences indicating the presence of phase transformations in the mixed cholesteryl benzoate (CBE) and cholesteryl butyrate (CBU) under the supercritical CO(2) pressurization, by means of differential scanning calorimetry (DSC) and X-ray diffraction (XRD), are presented in this work. These include (1) the DSC heating curve of pure CBU; (2) the DSC heating curves of CBU/CBE mixtures; (3) the XRD spectra of pure CBU; (4) the XRD spectra of CBU/CBE mixtures; (5) CBU and CBE are miscible in either solid phase or liquid phase over the whole composition range. As a result of the presence of these phase transformations induced by pressurization, it could be deduced that a solid solution of the CBU/CBE mixture might have formed at the interfaces under supercritical conditions, subsequently influencing their dissolving behaviors in supercritical CO(2).
Huang
Zhen
Z
Tianjin Key Laboratory of Refrigeration Technology, Department of Packaging Engineering, Tianjin University of Commerce, Tianjin 300134, China. huang900@yahoo.com
Feng
Mei
M
Su
Junfeng
J
Guo
Yuhua
Y
Liu
Tie-Yan
TY
Chiew
Yee C
YC
D002152:Calorimetry, Differential Scanning; D002245:Carbon Dioxide; D002788:Cholesterol Esters / Q000737:chemistry*; D025924:Chromatography, Supercritical Fluid; D003460:Crystallization; D044367:Phase Transition; D014961:X-Ray Diffraction
D002788:Cholesterol Esters; D002245:Carbon Dioxide; C092211:cholesteryl butanoate; C029808:cholesteryl benzoate