Search results for "Supercritical fluid"

Pressurized liquid extraction of organic contaminants in environmental and food samples

2015

Pressurized liquid extraction (PLE) is an automated technique that uses elevated temperature and pressure to achieve exhaustive extraction from solid matrices, so reducing solvent consumption and enhancing sample throughput when compared with traditional procedures. Hence, it can be considered an environment-friendly technique, generating small volumes of waste and reducing costs and time. This review focuses on application of this green technique to the analysis of organic contaminants in food and environmental matrices for monitoring purposes. We examine fundamentals and key aspects of the development of a PLE method, including pressurized hot-water extraction, together with some relevant…

Determination of pesticides and their degradation products in soil: critical review and comparison of methods

2004

18 páginas, 5 figuras, 5 tablas.

Supercritical CO2 extraction of essential oils from orange peel

1996

The supercritical fluid extraction of orange essential oil was studied using dehydrated orange peel (0.0538 kg H2O kg−1 dm) from naveline cultivars as raw material and CO2 as solvent. The effect of operation conditions was analyzed in a series of experiments at 313 and 323 K and pressures between 1 and 25 MPa. Furthermore, the effect of CO2 flow rate and particle size of orange peel was studied in the range of 0.5 to 3.5 kg h−1 and 0.1 to 10 mm. The subcritical CO2 dissolves hardly any essential oils, however, on reaching the critical point, the amount of essential oils dissolved increased with pressure, within the range of pressures considered in this study. Increasing solvent mass flow de…

Gas assisted mechanical expression (GAME) as a promising technology for oil and phenolic compound recovery from tiger nuts

2015

Abstract The aim of this work was to investigate the potential of gas assisted mechanical expression (GAME) process as an innovative technology for oil extraction and polyphenol recovery from tiger nuts. GAME process was first studied by varying the supercritical carbon dioxide (SC-CO2) and the mechanical expression (ME) pressures (10–30 MPa), then was compared to separate processes applied alone, using either SC-CO2 or ME. The results showed that the better conditions for GAME were found using 20 MPa for SC-CO2 and 30 MPa for ME. Under these conditions, 50% of oil was released from tiger nuts after 10 min extraction, compared to only 10% and 20% when using SC-CO2 and ME separately at 20 an…

Supercritical Fluid Adsorption of Domperidone on Silica Aerogel

2013

Silica aerogel (SA) was loaded with domperidone to demonstrate the potentiality of adsorption processes based on the usage of supercritical carbon dioxide to treat poorly water-soluble drugs, forming new kinds of drug delivery systems. The effects of pressure, temperature and solution concentration on loaded SA were studied. Adsorption isotherms were measured at 35℃ and 45℃ and fitted with Langmuir model. Release kinetics of the adsorbed drug were also evaluated by in vitro dissolution tests. Results showed that domperidone can be uniformly dispersed into the aerogel and that the release rate of domperidone from the composite, constituted by drug and silica aerogel, is much faster than that…

Solubility of some pesticides in supercritical CO2

1988

The solubility limits of some pesticides (Linuron, Methoxychlor, Diclofopmethyl, Diclofop and 2,4-D) and of 3,4-dichloroaniline have been determined in supercritical CO2 at 200 bar and 40° C, using the Milton Roy sample preparation accessory SPATM. Depending on the polarity and vapour pressure of the investigated compounds, the solubility was found to be between 0.3 and 12 gl−1.

Supercritical Fluid Extraction and Supercritical Fluid Chromatography of Vitamin E in Pharmaceutical Preparations

1999

Traditional and new analytical methodology

2010

International audience

Reversed Phase Liquid Chromatography

2015

Supercritical fluid extraction and high performance liquid chromatography determination of homosalate in lipsticks

2001

Supercritical fluid extraction of homosalate is reported for the first time. Extraction parameters such as pressure, time of extraction, use of modifier, temperature and sample mass were studied. The proposed method was assayed for the extraction of homosalate in sunscreen lipsticks. Efficient recoveries were obtained after 5 min of dynamic extraction with supercritical CO2 and 15% ethanol as modifier at 300 bar and 60°C, flow rate 4 mL min−1. Extracts were dissolved in ethanol, and homosalate determined by HPLC using water—acetic acid—ethanol mobile phase and flow rate of 1 mL min−1. UV detection was at 309 nm using homosalate in ethanol solutions as standards, limit of detection 4 μg mL−1…