Enhanced solvent extraction

In liquid-solid extraction (LSE) the analyte is extracted from the solid by a liquid, which is separated by filtration. Numerous extraction processes, representing various types and levels of energy, have been described steam distillation, simultaneous steam distillation-solvent extraction (SDE), passive hot solvent extraction, forced-flow leaching, (automated) Soxh-let extraction, shake-flask method, mechanically agitated reflux extraction, ultrasound-assisted extraction, y -ray-assisted extraction, microwave-assisted extraction (MAE), microwave-enhanced extraction (Soxwave ), microwave-assisted process (MAP ), gas-phase MAE, enhanced fluidity extraction, hot (subcritical) water extraction, supercritical fluid extraction (SFE), supercritical assisted liquid extraction, pressurised hot water extraction, enhanced solvent extraction (ESE ), solu-tion/precipitation, etc. The most successful systems are described in Sections 3.3.3-3.4.6. Other, less frequently... 

Hybrid Supercritical Fluid Extraction/ Enhanced Solvent Extraction... 

Principles and Characteristics In an attempt to develop a unified sample preparation system for extraction of various matrix/analyte combinations Ashraf-Khorassani et al. [498] have described a hybrid supercritical fluid extraction/enhanced solvent extraction (SFE/ESE ) system to remove both polar and nonpolar analytes from various matrices. The idea is that a single instrument that can perform extractions via pure C02 solvent, and all gradients thereof affords... 

ECCI Electron capture chemical ionisation ESE Enhanced solvent extraction... 

Hardcastle JL, Compton RG (2001) The electroanalytical detection and determination of copper in heavily passivating media ultrasonically enhanced solvent extraction by N-benzoyl-N-phenyl-hydroxylamine in ethyl acetate coupled with electrochemical detection by sono-square wave stripping voltammetry analysis. Analyst 126 2025-2031... 

NP Land applied sewage sludge Enhanced solvent extraction dichloromethane 126 [8]... 

Solvent extraction has long been established as a basic unit operation for chemical separations. Chapter 7 summarizes the effects of temperature, pH, ion pairs, and solvent selection on solvent extraction for biomolecules. Solvent extraction of fermentation products such as alcohols, aliphatic carboxylic acids, amino acids, and antibiotics are discussed. Enhanced solvent extraction using reversed micelles and electrical fields are also discussed. Solvent-extraction equipment and operational considerations are adequately covered in this chapter. 

Pressurized solvent extraction (PSE), also called pressurized fluid extraction (PEE), accelerated solvent extraction (ASE ), pressurized liquid extraction (PEE), or enhanced solvent extraction (ESE), is a solid-liquid extraction that has been developed as an alternative to conventional extractions such as Soxhlet, maceration, percolation, or reflux. It uses organic solvents at high pressure and temperature to increase the efficiency of the extraction process. Increased temperature decreases the viscosity of the liquid solvent, enhances its diffusivity, and accelerates the extraction kinetics. High pressure keeps the solvent in its liquid state and thus facilitates its penetration into the matrix, resulting in increase extraction speed [30]. 

Seabra, I.J. Braga, M.E.M. Batista, M.T. de Sousa, H.C. 2010. Effect of solvent (CO2/ ethanol/Fl20) on the fractionated enhanced solvent extraction of anthocyanins from elderberry pomace. J. Supercrit. Fluids 54 145-152. 

Zhou, L.Y. Asharf-Khorassani, M. Taylor, L.T. Comparison of methods for quantitative analysis of additives in low density polyethylene using supercritical fluid and enhanced solvent extraction. J. Chromatogr., A 1999, 858, 209-218. 

Lou, X., Janssen, H.G. and Cramers, C., Routine analysis of vinicutltural relevant fungicides, insecticides and herbicides in soil samples using enhanced solvent extraction (ESE), Anal. Chem., 1997, 69, 1598. 

Pressurized liquid extraction (PLE) is also known as pressurized solvent extraction (PSE), enhanced solvent extraction (ESE), pressurized fluid extraction (PEE), or accelerated solvent extraction (ASE ) in the literature. PLE is considered an environmentally friendly extraction technique because it requires only small volumes of solvents. PLE was primarily used for the extraction of environmental samples, such as soils and sediments. Elevated temperatures (usually between 50 and 200 °C) and pressures (between 10 and 15 MPa) are used in closed vessels, which allow extractions to be completed in a very short time. High pressure allows the solvent to remain in its liquid state even at temperatures above its boiling point, and forces it into the matrix pores. High temperatures decrease the solvent viscosity and increase metabolite solubilization, the diffusion rate, and mass transfer kinetics, thus facilitating desorption of the analytes from the plant material. Most PLE applications reported in the literature employ the same organic solvents as those commonly used in conventional solid-liquid extraction techniques. When water is used as the extraction solvent, the technique is referred to as pressurized hot water extraction (PHWE). Extractions are carried out in stainless steel extraction cells of various volumes (typically 1-250 mL). One extraction cycle is generally applied for 5-20 min at temperatures ranging from 50 to 140 °C in the vast majority of applications. 

Conventional methods for extracting oils involve three basic approaches physical, chemical and a combination of both. In all cases the fundamental mechanism is to rupture the cell structure of the oil-bearing plant or animal materials and subsequently or simultaneously remove the oil. Enzymes have found use in oil extraction and their applications can be categorized as enzymes that assist pressing, enzymes that enhance solvent extraction and enzymes that assist aqueous extraction. 

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