Optimization of supercritical CO2 extraction of Thymbra spicata oil

The supercritical fluid extraction (SFE) of aroma compounds from Thymbra spicata was studied. Response surface methodology (RSM) was used to optimize the parameters of the supercritical fluid extraction. Independent variables were temperature (40, 50 and 60 degreesC), pressure (80, 100 and 120 bar) and time (30, 60 and 90 min). Dependent variables were yield, monoterpene, sesquiterpene and oxygenated monoterpene contents.


Optimization of supercritical carbon dioxide extraction of antioxidants from roasted wheat germ based on yield, total phenolic and tocopherol contents, and antioxidant activities of the extracts
Gelmez, Niluefer; Kincal, N. Suzan; Yener, Meryem Esra (Elsevier BV, 2009-04-01)
Effects of pressure (148-602 bar), temperature (40-60 degrees C) and time (10-60 min) on antioxidant (phenolics and tocopherols) contents and antioxiclant activities of supercritical carbon dioxide (SC-CO2) extracts of roasted wheat germ were determined, using central composite rotatable design. The dependent variables were yield (%), total phenolic contents (TPC, mg gallic acid equivalent (GAE)/g extract), total tocopherol contents (TTC, mg tocopherol/g extract) and antioxidant activities (AA, mg scavenged...
Enhanced solubility of siloxy-modified polyhedral oligomeric silsesquioxanes in supercritical carbon dioxide
Demirtas, Cansu; Dilek Hacıhabiboğlu, Çerağ (Elsevier BV, 2019-01-01)
Alkyl siloxy functionalization increases the solubility of polyhedral oligomeric silsesquioxanes (POSS) in supercritical carbon dioxide over an order of magnitude compared to its counterpart with fluoroalkyl groups. The studied component, octatrimethylsiloxy POSS also exhibits higher solubility than other previously studied POSS types with various alkyl and methacryl groups. The octatrimethylsiloxy POSS-CO2 solid-vapor equilibrium curves have been constructed at temperatures between 308 and 328 K by measuri...
Phase behavior of 1,3,5-tri-tert-butylbenzene-carbon dioxide binary system
Dilek Hacıhabiboğlu, Çerağ; Gulari, Esin (Elsevier BV, 2008-01-01)
1,3,5-tri-tert-butylbenzene (TTBB) is solid at ambient conditions, and has substantial solubility in liquid and supercritical carbon dioxide. We present the phase behavior of TTBB-CO2 binary system at temperatures between 298 and 328 K and at pressures up to 20 MPa. Phase diagrams showing the liquid-vapor, solid-liquid and solid-vapor equilibrium envelopes are constructed by pressure-volume-temperature measurements in a variable-volume sapphire cell. TTBB is highly soluble in CO2 over a wide range of compos...
Supercritical CO2 intercalation of layered silicates
Serhatkulu, Gulay; Dilek Hacıhabiboğlu, Çerağ; Gulari, Esin (Elsevier BV, 2006-12-01)
In this study, we use supercritical CO2 as the processing medium for intercalating the structure of natural clay, Cloisite Na+, and depositing CO2-philic sugar acetate, P-D-galactose pentaacetate, between the layers of the clay. Based on our measurements of the phase behavior of the P-D-galactose pentaacetate-CO2 system, we select two processing conditions: a dense gas solution (DGS) at 40 degrees C and 11.7 MPa with 2.4 wt.% sugar acetate in CO2 and a gas-expanded liquid (GEL) at 40 degrees C and 7.9 MPa w...
Dynamic and steady-state analysis of oxidative dehydrogenation of ethane
Karamullaoğlu, Gülsün; Doğu, Timur; Department of Chemical Engineering (2005)
In this research, oxidative dehydrogenation of ethane to ethylene was studied over Cr-O and Cr-V-O mixed oxide catalysts through steady-state and dynamic experiments. The catalysts were prepared by the complexation method. By XRD, presence of Cr2O3 phase in Cr-O; and the small Cr2O3 and V2O4 phases of Cr-V-O were revealed. In H2-TPR, both catalysts showed reduction behaviour. From XPS the likely presence of Cr+6 on fresh Cr-O was found. On Cr-V-O, the possible reduction of V+5 and Cr+6 forms of the fresh sa...
Citation Formats
S. Sonsuzer, S. Şahin, and L. Yılmaz, “Optimization of supercritical CO2 extraction of Thymbra spicata oil,” JOURNAL OF SUPERCRITICAL FLUIDS, pp. 189–199, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/44283.