The Experts below are selected from a list of 111 Experts worldwide ranked by ideXlab platform
Bruno Marongiu - One of the best experts on this subject based on the ideXlab platform.
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Comparative analysis of the oil and supercritical CO2 extract of Ridolfia segetum (L.) Moris.
Natural product research, 2007Co-Authors: Bruno Marongiu, Silvia Porcedda, Alessandra Piras, Enrica Tuveri, Andrea MaxiaAbstract:Supercritical carbon dioxide extraction allowed to obtain the volatile oil of different aerial parts of Ridolfia segetum (L.) Moris. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 degrees C and carbon dioxide flow, Phi = 1.0 kg h(-1). Waxes were entrapped in the first separator set at 90 bar and -10 degrees C. The oil was recovered in the second separator working at 15 bar and 10 degrees C. The main components of the flower oil were alpha-phellandrene (19.4%), terpinolene (20.5%), piperitenone oxide (11.6%), beta-phellandrene (8.2%), (Z)-beta-ocimene (7.8%), myristicin (7.5%) and p-cymene (4.4%). The comparison with the hydrodistilled (HD) oil reveal that the significative difference was the content of sesquiterpenes which are higher in the supercritical fluid extraction (SFE) products. Collection of samples at different extraction times during supercritical extraction, allowed to monitor the change of the oil composition. Lighter compounds, as Hydrocarbon monoterpenes, were extracted in shorter times than the Heavier Hydrocarbon and oxygenated sesquiterpenes. The oil from the steams was characterized by a high content of alpha-phellandrene (12.9%), terpinolene (11.6%), myristicin (11.0%), p-cymene (9.9%), beta-phellandrene (8.2%) and (Z)-beta-ocimene (6.0%) while the main components of the fruits were found to be myristicin (70.8%), piperitenone oxide (19.9%) and dill apiole (4.2%).
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chemical composition of the oil and supercritical co2 extract of schinus molle l
Flavour and Fragrance Journal, 2004Co-Authors: Bruno Marongiu, Alessandra Piras Silvia Porcedda, Rita Casu, Paola PierucciAbstract:Supercritical carbon dioxide extraction allowed Schinus molle L. volatile oil to be obtained. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 °C, carbon dioxide flow, Φ = 1.0 kg/h. Waxes were entrapped in the first separator set at 90 bar and -10 °C. The oil was recovered in the second separator, working at 15 bar and 10 °C. The main components were α-phellandrene (26.5%), limonene + β-phellandrene (21.0%), elemol (10.8%) and α-eudesmol (6.1%). Comparison with the hydrodistilled oil (HD) did not reveal any large difference, whereas the significant difference between the SFE and SD oils was the content of sesquiterpenes, which is higher in the SFE products. Collection of samples at different extraction times during supercritical extraction allowed changes of the oil composition to be monitored. Lighter compounds, as Hydrocarbon monoterpenes, were extracted in shorter times than the Heavier Hydrocarbon and oxygenated sesquiterpenes. Copyright © 2004 John Wiley & Sons, Ltd.
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Supercritical carbon dioxide extraction and characterization of Laurus nobilis essential oil.
Journal of agricultural and food chemistry, 2002Co-Authors: Alessandra Caredda, Bruno Marongiu, Silvia Porcedda, Carla SoroAbstract:Supercritical carbon dioxide extraction allowed essential oil of Laurus nobilis to be obtained. Extraction conditions were as follows: pressure, 90 bar; temperature, 50 °C; and carbon dioxide flow, Φ = 1.0 kg/h. Waxes were entrapped in the first separator set at 90 bar and −10 °C. The oil was recovered in the second separator working at 15 bar and 10 °C. The main components were 1,8-cineole (22.8%), linalool (12.5%), α-terpinyl acetate (11.4%), and methyleugenol (8.1%). Comparison with the hydrodistilled oil did not reveal any significant difference. Collection of samples at different extraction times during supercritical extraction allowed the change of the oil composition to be monitored. Lighter compounds such as Hydrocarbon and oxygenated monoterpenes were extracted in shorter times than the Heavier Hydrocarbon and oxygenated sesquiterpenes. Keywords: Supercritical carbon dioxide extraction; essential oil; Laurus nobilis
Dimitrios P. Tassios - One of the best experts on this subject based on the ideXlab platform.
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MethaneHydrocarbon interaction parameters correlation for the Peng-Robinson and the t-mPR equation of state
Fluid Phase Equilibria, 1995Co-Authors: Aris Kordas, Kostis Magoulas, Sofia Stamataki, Dimitrios P. TassiosAbstract:Abstract Generalized expressions for the interaction coefficients (kij) of CH 4 Hydrocarbon binary systems are presented for a modified and translated Peng-Robinson equation of state (t-mPR). The correlations involve the acentric factor of the Heavier Hydrocarbon and cover the CH 4 n- alkane systems up to n-C44 plus isomers and cycloalkanes. Typical errors in bubble point pressure predictions are below 5%, similar to those obtained by fitting the T-P-x data. Successful predictions of saturated liquid and vapor volumes are also obtained. For the CH 4 non-alkane systems average kij values are recommended, since the lack of data for an adequate number of systems does not allow the development of a generalized correlation. The proposed correlations can be used with the Peng-Robinson equation of state as well.
Pal Skalle - One of the best experts on this subject based on the ideXlab platform.
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Effect of extended Heavier Hydrocarbon fraction (Cn+) composition on optimum surface separation pressure and temperature
Journal of Petroleum and Gas Engineering, 2018Co-Authors: Juvencio Armando Massinguil, Lu Is Helder Lucas, Pal SkalleAbstract:Hydrocarbon fluids are made up of defined components which include N2, CO2, H2S, C1, C2, C3, iC4, iC5, and C6 and undefined components known as Heavier fractions (Cn+) which include paraffinic, naftenic and aromatic compounds. The Hydrocarbons are separated on the surface before they are sent to the market. There are several factors affecting the Hydrocarbons surface separation condition which include; pressure, temperature, gas liquid flow rates, surging or slugging tendencies of the feed stream, presence of impurities such as paraffin and sands. This work is limited to the study of the effects of pressure and temperature. To obtain stabilized Hydrocarbons phases optimum surface separation, pressure and temperature must be selected. Several empirical models have been developed to obtain optimum surface separation pressure and temperature. However, these models do not consider the full composition of the well stream, and the Heavier fractions are most often treated as a single component. This paper presents the estimation of an optimum surface separation-pressure and temperature of crude oil while including the complete composition of the well stream and extended composition of the Heavier fraction. The optimum pressure was estimated through the fluid properties such as oil formation volume factor, gas oil ratio and API gravity. Optimum pressure and temperature is the one that produces maximum liquid yield (by minimizing oil formation volume factor and gas oil ratio) of maximum quality (by maximizing API gravity). The fluid properties were predicted by phase equilibrium calculations using Peng Robinson thermodyinamic Model. The optimum pressure was first estimated considering the Heavier fraction as single component and second the Heavier fraction was splitted in pseudo components, both including the full composition of the well stream. Ahmed splitting method was used to extend the Heavier fraction compostion, Kesler and Lee’s correlation was apllied to assign critical properties of the pseudo components. The results indicate that it is possible to estimate more accurately the optimum separation pressure by extending a composition of Heavier fraction and accurate values of fluid properties were obtained. Key words: C7+ fraction, splitting scheme, equation of state, Peng-Robison thermodynamic model, optimum separator pressure.
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effect of extended Heavier Hydrocarbon fraction cn composition on optimum surface separation pressure and temperature
Journal of Petroleum and Gas Engineering, 2018Co-Authors: Juvencio Armando Massinguil, Lu Is Helder Lucas, Pal SkalleAbstract:Hydrocarbon fluids are made up of defined components which include N2, CO2, H2S, C1, C2, C3, iC4, iC5, and C6 and undefined components known as Heavier fractions (Cn+) which include paraffinic, naftenic and aromatic compounds. The Hydrocarbons are separated on the surface before they are sent to the market. There are several factors affecting the Hydrocarbons surface separation condition which include; pressure, temperature, gas liquid flow rates, surging or slugging tendencies of the feed stream, presence of impurities such as paraffin and sands. This work is limited to the study of the effects of pressure and temperature. To obtain stabilized Hydrocarbons phases optimum surface separation, pressure and temperature must be selected. Several empirical models have been developed to obtain optimum surface separation pressure and temperature. However, these models do not consider the full composition of the well stream, and the Heavier fractions are most often treated as a single component. This paper presents the estimation of an optimum surface separation-pressure and temperature of crude oil while including the complete composition of the well stream and extended composition of the Heavier fraction. The optimum pressure was estimated through the fluid properties such as oil formation volume factor, gas oil ratio and API gravity. Optimum pressure and temperature is the one that produces maximum liquid yield (by minimizing oil formation volume factor and gas oil ratio) of maximum quality (by maximizing API gravity). The fluid properties were predicted by phase equilibrium calculations using Peng Robinson thermodyinamic Model. The optimum pressure was first estimated considering the Heavier fraction as single component and second the Heavier fraction was splitted in pseudo components, both including the full composition of the well stream. Ahmed splitting method was used to extend the Heavier fraction compostion, Kesler and Lee’s correlation was apllied to assign critical properties of the pseudo components. The results indicate that it is possible to estimate more accurately the optimum separation pressure by extending a composition of Heavier fraction and accurate values of fluid properties were obtained. Key words: C7+ fraction, splitting scheme, equation of state, Peng-Robison thermodynamic model, optimum separator pressure.
Erik Gydesen Sogaard - One of the best experts on this subject based on the ideXlab platform.
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application of gc ms chromatography for the analysis of the oil fractions extracted by supercritical co2 at high pressure
Fuel, 2013Co-Authors: Svetlana Nikolayevna Rudyk, Pavel Spirov, Erik Gydesen SogaardAbstract:Abstract GC–MS chromatographic analysis has been applied for the investigation of the fractions of oil extracted by supercritical carbon dioxide at a temperature of 60 °C and at pressure values ranging from 22 to 56 MPa. The observations revealed, that the whole extraction process is clearly reflected in the chromatograms, demonstrating how the Heavier Hydrocarbon fractions were gradually involved in the extraction process. The shape of the chromatograms alters with increasing pressure from triangle to trapezoid, approaching the shape of the chromatogram of the crude oil. The observation of the fingerprints of chromatograms allows them to be used for the qualitative evaluation of extraction progression. It can also be noticed, that the area under the spectrum of the chromatograms of oil samples extracted at various pressures is increasing with an increase in pressure. The oil recoveries, evaluated as the ratio of the area under the spectrum or the baseline of the chromatogram of the sample extracted at the specific pressure value to the area under the spectrum or the baseline of the chromatogram of the crude oil, showed a close correlation with the oil recoveries obtained from the experiment. This allows the use of the chromatographic method for the quantitative evaluation of oil recovery.
Aris Kordas - One of the best experts on this subject based on the ideXlab platform.
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MethaneHydrocarbon interaction parameters correlation for the Peng-Robinson and the t-mPR equation of state
Fluid Phase Equilibria, 1995Co-Authors: Aris Kordas, Kostis Magoulas, Sofia Stamataki, Dimitrios P. TassiosAbstract:Abstract Generalized expressions for the interaction coefficients (kij) of CH 4 Hydrocarbon binary systems are presented for a modified and translated Peng-Robinson equation of state (t-mPR). The correlations involve the acentric factor of the Heavier Hydrocarbon and cover the CH 4 n- alkane systems up to n-C44 plus isomers and cycloalkanes. Typical errors in bubble point pressure predictions are below 5%, similar to those obtained by fitting the T-P-x data. Successful predictions of saturated liquid and vapor volumes are also obtained. For the CH 4 non-alkane systems average kij values are recommended, since the lack of data for an adequate number of systems does not allow the development of a generalized correlation. The proposed correlations can be used with the Peng-Robinson equation of state as well.