Matrix effects in supercritical CO2 extraction of essential oils from plant material (original) (raw)
Related papers
2007
In this study, the supercritical carbon dioxide extraction of essential oils from plants which contain secretory ducts as essential oil reservoirs was investigated and modelled. Supercritical carbon dioxide extraction of essential oils from Asteraceae family species, marigold and chamomile, indicated that particle size had no significant influence on the extraction rate in two outermost cases: fine milled plant material and plant material cut to particle length of 5 mm. This confirmed previously reported phenomenon that in some cases particle size had no influence on the rate of supercritical extraction process. In order to explain this behavior, the mathematical model which took into consideration the phenomena occurring on the secretory duct scale, was developed and applied to simulate experimental data of marigold and chamomile supercritical carbon dioxide extraction. Proposed model was also applied to the literature experimental data of fennel fruit supercritical fluid extraction where the same phenomenon had been observed. To obtain information regarding secretory structure, scanning electron microscopy investigation of the plant material was performed. Very good agreement of the model results and experimental data in the case of different plant species, extraction conditions and particle sizes, confirmed the basic hypothesis of the model.
Supercritical carbon dioxide extraction of essential oils:: Modeling and simulation
Chemical engineering science, 1998
In this study, the supercritical carbon dioxide extraction of essential oils from plants which contain secretory ducts as essential oil reservoirs was investigated and modelled. Supercritical carbon dioxide extraction of essential oils from Asteraceae family species, marigold and chamomile, indicated that particle size had no significant influence on the extraction rate in two outermost cases: fine milled plant material and plant material cut to particle length of 5 mm. This confirmed previously reported phenomenon that in some cases particle size had no influence on the rate of supercritical extraction process. In order to explain this behavior, the mathematical model which took into consideration the phenomena occurring on the secretory duct scale, was developed and applied to simulate experimental data of marigold and chamomile supercritical carbon dioxide extraction. Proposed model was also applied to the literature experimental data of fennel fruit supercritical fluid extraction where the same phenomenon had been observed. To obtain information regarding secretory structure, scanning electron microscopy investigation of the plant material was performed. Very good agreement of the model results and experimental data in the case of different plant species, extraction conditions and particle sizes, confirmed the basic hypothesis of the model.
The Co 2 Density Variation in the Supercritical Extraction of Anet Essential Oils
2007
abstract: The supercritical fluid extraction of anet essential oil was studied using CO2 as solvent. The effect of CO2 density variation in the range of 0.225 g/ml to 0.662 g/ml was analyzed. Chemical analysis revealed that oils extracted under different supercritical CO2 extraction conditions possessed a different percentage composition. Oil obtained by hydrodistillation was also compared with the extracted oils.
Mathematical modelling of supercritical CO2 extraction of volatile oils from aromatic plants
Chemical Engineering Science, 2010
The modelling of the experimental data of the extraction of the volatile oil from six aromatic plants (coriander, fennel, savoury, winter savoury, cotton lavender and thyme) was performed using five mathematical models, based on differential mass balances. In all cases the extraction was internal diffusion controlled and the internal mass transfer coefficient (k s ) have been found to change with pressure, temperature and particle size. For fennel, savoury and cotton lavender, the external mass transfer and the equilibrium phase also influenced the second extraction period, since k s changed with the tested flow rates.
The Journal of Supercritical Fluids, 2014
Bed geometry plays an important role in supercritical fluid extraction kinetics. Thus, the objective of this study was to compare the overall extraction curves (OEC's) of rosemary compounds obtained in two beds of 1 L each with different geometries (in terms of height to bed (H B ) diameter (D B ) ratios, H B /D B ). A scale-up study was carried out maintaining the solvent mass to feed mass (S/F) ratio equal for both beds. Other process variables, such as bed porosity, apparent and true densities of the raw material, particle average size, temperature, pressure and time of extraction, were also maintained constant. The kinetic parameters were obtained by fitting the OEC to a spline model. The results revealed differences of mass transfer rates, mass ratios of solute in the fluid phase and yields of extract in the constant extraction rate period. The evaluation of the OEC's and kinetic parameters indicated that the bed with lower H B /D B ratio (H B /D B = 2.7) was more favorable for obtaining rosemary extract. The kinetics of extraction of oxygenated monoterpenes (i.e., 1,8-cineole and camphor) and phenolic diterpenes (i.e., carnosic acid) were also different for both bed geometries. These behaviors suggest that the bed geometry presents a pronounced influence in the mass transport properties in supercritical media. Thus, in spite of the scale-up criterion be successful for several botanic matrices such as clove buds, sugarcane residue and grape seeds residue, the criterion applied in this study (maintaining a constant S/F ratio for a given time of extraction) was not suitable for this raw material.
Critical review of supercritical fluid extraction of selected spice plant materials
Macedonian Journal of Chemistry and Chemical Engineering
Supercritical fluid extraction (SFE) is one of the relatively new efficient separation method for the extraction of essential oils from different plant materials. The new products, extracts, can be used as a good base for the production of pharmaceutical drugs and additives in the perfume, cosmetic, and food industries. The aim of this work was to analyze the supercritical carbon dioxide extraction (SC-CO2) of oils from the selected spice plant materials. In this paper the process parameters such as pressure, temperature, solvent flow rate, size of grinding materials, and ratio of the co-solvent were presented for the selected spice plant materials: black pepper, caraway, celery, cinnamon, clove, coriander, daphne, fennel, ginger, hyssop, juniper, lavender, oregano, pennyroyal, red pepper, safflower, sage, turmeric, and vanilla. The values of operating conditions were: pressure from 7.5 to 68 MPa, temperature from 293 to 363 K, solvent flow rate from 0.003 to 30.0 kg/h, and diameter...
An overview of the studies carried out in our laboratories on supercritical fluid extraction (SFE) of volatile oils from seven aromatic plants: pennyroyal (Mentha pulegium L.), fennel seeds (Foeniculum vulgare Mill.), coriander (Coriandrum sativum L.), savory (Satureja fruticosa Béguinot), winter savory (Satureja montana L.), cotton lavender (Santolina chamaecyparisus) and thyme (Thymus vulgaris), is presented. A flow apparatus with a 1 L extractor and two 0.27 L separators was built to perform studies at temperatures ranging from 298 to 353 K and pressures up to 30.0 MPa. The best compromise between yield and composition compared with hydrodistillation (HD) was achieved selecting the optimum experimental conditions of extraction and fractionation. The major differences between HD and SFE oils is the presence of a small percentage of cuticular waxes and the relative amount of thymoquinone, an oxygenated monoterpene with important biological 10551 properties, which is present in the oils from thyme and winter savory. On the other hand, the modeling of our data on supercritical extraction of volatile oil from pennyroyal is discussed using Sovová's models. These models have been applied successfully to the other volatile oil extractions. Furthermore, other experimental studies involving supercritical CO 2 carried out in our laboratories are also mentioned.
Energy Procedia, 2012
In this work essential oil was extracted from Algerian Rosemary leaves by the supercritical CO 2 extraction. The effects of the key parameters such as pressure and temperature on the yield of extraction were examined. The obtained yield were in the range of 0.95-3.52 g of dry oil / g of rosemary, and the best value was obtained at a pressure of 22 MPa and temperature of 40°C. The model of shrinking-core was used to analyse the experimental results of the extraction, this model contains one adjustable parameter, effective diffusivity De, the experimental results were successfully fitted.