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Separation technologies/processes supercritical extraction

Due to possible environmental problems with acetone, new technologies are being developed for the production of deoiled lecithins involving treatment of Hpid mixtures with supercritical gases or supercritical gas mixtures (10—12). In this process highly viscous cmde lecithin is fed into a separation column at several levels. The supercritical extraction solvent flows through the column upward at a pressure of 8 MPa (80 bar) and temperature between 40 and 55°C. The soy oil dissolves together with a small amount of lecithin. [Pg.100]

One of the most studied technologies is supercritical fluid extraction with SC-CO2. The advantages of SC-CO2 include its low processing temperature, which minimizes thermal degradation the ease of separation with no solvent residue left in the final product and minimization of undesirable oxidation reactions. [Pg.236]

Separation Technology Keep an Eye on Chemical Process, 1985 Supercritical Extraction... [Pg.2]

Supercritical fluid extraction of emulsions (SFEE) is a combination of the conventional emulsion precipitation process with the SAS processes. This process emerges as a solution for several of the drawbacks of each separated technology. Conventional emulsion precipitation methods involve large quantities of organic solvents and their removal requires additional separation techniques that commonly need high temperatures and high cost. On the other hand, as shown in Table 24.1 by SAS process, often it is not possible to obtain particle sizes within the nanometric scale and the products can present agglomeration problems. [Pg.452]

The current state of analytical SPE was critically reviewed and no major changes of the technique have been observed. Overviews of the developments of the extraction technologies of secondary metabolites from plant materials refer to three types of conventional extraction techniques that involve the use of solvents, steam, or supercritical fluids. Each technique is described in detail with respect to typical processing parameters and recent developments. Eollowing the discussion of some technical and economic aspects of conventional and novel separation processes, a few general conclusions about the applicabilities of the different types of extraction techniques are drawn. ... [Pg.305]

In the last years supercritical fluid (SCF) technology has occupied a significant place in the high pressure chemical engineering. Due to their specific properties as liquid-like densities, gas-like viscosities and diffusivities intermediate between gas and liquid values, SCF have large potential in extraction and separation processes, polymer science and technology and in elaboration of new materials [1-4], In these last cases, to control the size of particles, we have to deal with the kinetics of their formation. ... [Pg.389]

The application of supercritical fluids, for example SCCO2, as an environmentally acceptable replacement for conventional solvents, is well documented in the industry. Based on the work of Zosel, the decaffeination of coffee and tea using SCCO2 was the first industrial use of this technology [1]. The advantages of supercritical fluids are not only useful in separation techniques, for example supercritical fluid extraction (SFE) or supercritical chromatography (SFC), their application as process solvents is well recognized [2, 3]. [Pg.398]

Different uses of supercritical fluid (SCF) solvents in chemical separation processes have been of considerable research interest since the 1970s. The basic principles of SCF extraction engineering and a number of applications for this technology are described in several review papers [1,2]. As a new field related to SCF technology, the application of supercritical solvents as reaction media attracts increasing attention, especially for catalytic reactions. In such processes, the SCF may either actively participate in the reaction or function solely as the solvent for the reactants, catalysts, and products. [Pg.388]

This new extraction technology appears promising for effective processing with marked reduction in waste generation because no aqueous solutions and organic solvents are involved and phase-separation can be easily achieved by depressurization. Recently, the authors found a CO soluble TBP complex with nitric acid was very effective for dissolution of UO2 and U30g and extracted as U02(N03)2(TBP)2 in supercritical CO2 (SF-C02)(8-ii). [Pg.11]

Based on the polarity difference between CO2 and the interior of the micelles, w/c microemulsions have found many applications as extraction media. Furthermore, by modifying pressure and temperature, solvent quality may be changed and it becomes, therefore, possible to exert a real control over the extraction process uptake of solutes inside micelles may be varied. This may be of use for separations/extractions involving bio-chemicals and proteins. In conventional solvents their separation from the reaction medium can be quite complicated, involving tedious processes such as fluid-fluid extraction, decantation, chromatography column, filtration, precipitation. Use of supercritical fluid technology with extraction in reverse micelles seems advantageous for proteins (e.g. 19, 76). This process was also used for the extraction of metals (77-79) and more recently of copper from a filter paper surface (1). [Pg.291]

In 2010 and 2012 All-Russian School-Conference of Young Scientists Supercritical Fluid Technologies in the Decision of Environmental Problems. Plants Biomass Extraction was held on the base of North (Arctic) Federal University. Taking into account the major local directions of scientific work, the scope of the School-Conference included sueh issues as the properties of supercritieal fluids, ScF extraction of plant biomass, chemical and biological processes in ScF media, ScF chromatography in analysis and separation of natural extracts. [Pg.243]


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Extractants separation

Extraction , separations

Extraction process

Extraction processing technology

Extractive processes

Extractive separations

Processing extraction

Processing separation

Separation processes

Separation technologies

Separation technologies/processes

Supercritical extractants

Supercritical extraction

Supercritical extraction process

Supercritical processes

Supercritical processing

Supercritical technology

Technological process

Technology processability

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