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Showing 1 to 20 of 25 for “"supercritical fluid extraction (SFE)"”.
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Determination of Extractables from Cranberry Seeds Using Supercritical CO₂
An alternative method for extraction of therapeutically beneficial compounds such as sterols, fatty acids, and tocopherols from cranberry seeds with pure SF CO2 has been provided. The supercritical fluid extraction (SFE) operating conditions such as extraction temperature, pressure of CO2, …
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Evaluation of conditions for quantitative recovery of a drug from animal feed using supercritical fluid CO₂ extraction
Supercritical fluid extraction (SFE) continues to be explored as a feasible alternative to traditional Soxhlet and other types of extraction. In many cases SFE is cleaner, faster, and less expensive than the traditional types of extractions. This investigation has focused on the evaluation of …
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Extraction of Additives from Polystyrene and Subsequent Analysis
The extraction of fifteen (15) polymer additives with supercritical carbon dioxide which are used as antioxidants, uv stabilizers, process lubes, flame retardants and antistats from eight formulations of polystyrene is demonstrated and compared to traditional dissolution/precipitation extractions. …
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Supercritical fluid extraction of polychlorinated biphenyls and organochlorine pesticides from mussel tissue (Mytilus edulis)
The supercritical fluid extraction (SFE) of twenty one polychlorinated biphenyls (PCBs) and eight organochlorine pesticides (OCPs) from freeze dried mussel tissue is discussed, demonstrated, and compared to traditional Soxhlet extractions. The aim of this study was to determine the efficacy of SFE …
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Aspects of the microwave induced plasma as an element selective detector for supercritical fluid chromatography and supercritical fluid extraction
The introduction of supercritical CO₂ at packed column supercritical fluid chromatography (SFC) flow rates is shown to significantly affect the excitation characteristics of a helium microwave induced plasma (He MIP). In this work, the influence of CO₂ on specific atomic and ionic transitions of …
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Liquid collection efficiencies after supercritical fluid extraction
The design of any supercritical fluid extraction (SFE) experiment should break down into two parts: 1) removal of the analytes of interest from the bulk matrix and 2) deposition of those analytes in a user friendly manner for further studies (spectroscopy or chromatography). While great attention …
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Investigation of the supercritical fluid extraction and detection of metals in contaminated soils
In this work the Supercritical Fluid Extraction (SFE) and detection of sorbed metals in contaminated soils is explored. Iron containing samples were spiked onto sea sand and extracted with Supercritical Fluid CO₂. On-line detection was accomplished by decompressing the SF-CO₂ and analyte into a …
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Development of Methods for the Determination of Major and Minor Elements and Hydrocarbon Residues in Solid Combustion Products
… by glow discharge spectrometry (GDS) and for the extraction of the organic compounds from coal and ash by supercritical fluid extraction (SFE) at temperatures below 150°C are reviewed. The inorganic elements studied included Al, Ca, C, Cu, Fe, Mg, Mn, P, S, Si and Ti. The organic compounds were …
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Quantitative Analysis of Additives in Low Density Polyethylene Using On-line Supercritical Fluid Extraction /Supercritical Fluid Chromatography
… products. Traditional liquid solvent/polymer extraction methods, which involve dissolution/precipitation, are time-consuming, uneconomical, and the recoveries are significantly lower than 90%. In recent years, analysis with supercritical fluids (SFs) has emerged as an alternative analytical …
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Supercritical Fluid Extraction and Chromatography of Various Lipids from Soybean Lecithin
… and phosphatidylserine have been studied by supercritical fluid chromatography (SFC) coupled with evaporative light scattering detection (ELSD) and mass spectrometry (MS). Four different silica-based stationary phases were studied: 2-ethylpyridine, 4-ethylpyridine, diol and conventional …
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Environmentally Benign Extraction Processes in Analytical Separation of Essential Oils
<p>Supercritical fluid extraction (SFE) technology has been well received as an environmentally friendly processing technique. Over the last two decades, its use in many processing industries has tremendously advanced. This is as a result of pressure from regulating bodies aimed at reducing the …
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Quantitative Analysis of Antioxidants from High Density Polyethylene (HDPE) by off-line Supercritical Fluid Extraction Coupled High Performance Liquid Chromatography
… the physical nature of the polymer. Conventional extraction techniques for polymer additive(s), such as, Soxhlet or dissolution / precipitation are labor intensive, time consuming, expensive, and the optimal recovery is significantly less than 90 percent. In addition, a large amount of solvent , …
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Supercritical Fluid Extraction of Nylon 6,6 Fiber Finish and Oligomers
… led to investigations of alternate methods of extraction. Several studies have shown that supercritical fluid extraction (SFE) using carbon dioxide as the extraction fluid is an important alternative to conventional organic solvent extraction for the removal of both textile finishes and …
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Supercritical fluid extraction as a sample preparation technique for the isolation of polar pharmaceutical compounds
The low polarity of the supercritical fluid extraction (SFE) solvent, CO₂, causes problems when applying this technique to polar compounds. The objective of this research was to expand the applicability of SFE to include polar compounds. The first phase of this research investigated "inverse SFE", …
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Supercritical fluid extraction applied to environmental pollutants from Chesapeake Bay sediment
Sample preparation via supercritical fluid extraction (SFE) has been increasingly used to determine polynuclear aromatic hydrocarbons (P AHs) in environmental samples. As an alternative sample preparation technique, SFE offers the distinct advantages of greatly reduced sample preparation time, …
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Investigation of Liquid Trapping Following Supercritical Fluid Extraction
Supercritical fluid extraction (SFE) is an alternative to traditional extractions with organic solvents. SFE consists of removing the analyte(s) from the matrix, solubilizing them, moving the analyte(s) into the bulk fluid, and sweeping the fluid containing the analyte(s) out of the extraction …
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Optimal Analysis of Sulfonamides From Biological Matrices Using Supercritical Fluids
… the effect of temperature and pressure on the supercritical fluid extraction (SFE) of sulfonamides from a spiked sand matrix. Temperature effects were either positive or negative with respect to extraction rate and total recovery, depending on the pressure and extraction fluid employed. The …
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Supercritical fluid extraction/chromatography and Fourier transform infrared spectrometry: methods optimization and applications
This work examines the use of supercritical fluid extraction (SFE)as a sample introduction technique for supercritical fluid chromatography (SFC) and Fourier transform infrared spectrometry (FT-IR). In order to study the effects of a supercritical mobile phase on the resulting IR spectra, carbon …
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Hyphenated fourier transform infrared spectrometry: techniques for separations and analysis
… FT-IR techniques specifically involving supercritical fluid extraction (SFE), supercritical fluid chromatography (SFC), and liquid chromatography (LC). Three studies are presented. The first involves the application of SFE/FT-IR towards the extraction of finishes from textile fibers. SFE …
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The extraction of analytes from aqueous solution using supercritical fluids
Supercritical fluid extraction (SFE) is becoming an attractive alternative to conventional solvent extraction for many reasons. These reasons include advantages of speed, the ability to be automated more easily than conventional solvent extractions and the lack of solvent disposal after the …
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