Extraction solvents for

Carbon disulphide is an excellent solvent for fats, oils, rubber, sulphur, bromine and iodine, and is used industrially as a solvent for extraction. It is also used in the production of viscose silk, when added to wood cellulose impregnated with sodium hydroxide solution, a viscous solution of cellulose xanthate is formed, and this can be extruded through a fine nozzle into acid, which decomposes the xanthate to give a glossy thread of cellulose. 

Aromatic Hydrocarbons. Sulfolane is used principally as a solvent for extraction of benzene, toluene, and xylene from mixtures containing aHphatic hydrocarbons (33—37). The sulfolane process was introduced in 1959 by SheU Development Company, and that process is Hcensed by Universal OH Products. A sulfolane extraction process is also Hcensed by the Atlantic Richfield Company. In 1994, worldwide consumption was estimated at ca 6974 t/yr of sulfolane for 137 sulfolane extraction units (see Bix processes Extraction, liquid-liquid Xylenes and ethylbenzene). 

Solvent extraction removes harmful constituents such as heavy aromatic compounds from lubricating oils to improve the viscosity-temperature relationship. The usual solvents for extracting lubricating oil are phenol and furfural. 

Ionic liquids as solvents for extraction Ionic liquid/aqueous Rogers et al. Dietz et al. Dai et al. 12, 13, 14, 15 16 17... 

Acetonitrile and hydrogen cyanide are hy-products that may he recovered for sale. Acetonitrile (CH3CN) is a high polarity aprotic solvent used in DNA synthesizers, high performance liquid chromatography (HPLC), and electrochemistry. It is an important solvent for extracting butadiene from C4 streams. Table 8-1 shows the specifications of acrylonitrile, HCN, and acetonitrile. ... 

The choice of solvent for extraction is governed by the following considerations. 

The polarity index is a measure of the polarity of the solvent, which is often the most important factor in the solvent choice for the particular application. In extraction processes, the tenet that like dissolves like (and conversely, opposites do not attract ) is the primary consideration in choosing the solvent for extraction, partitioning, and/or analytical conditions. For example, hexane often provides a selective extraction for nonpolar analytes, and toluene may provide more selectivity for aromatic analytes. 

In the first experiment the contaminated extracts were obtained and then they were thermally treated by plasma. The analytical results showed that the best solvents for extraction of oil - PCB s were isooctane, cyclohexane, isopropyl alcohol and their mixture. We have found the average extraction efficiency 95%. The best result 96.2% of the extraction efficiency we obtained for the mixture of isooctane and isopropyl alcohol in the ratio 1 1. 

Using the individual solvents as blanks, acquire a visible absorption spectrum of each sample. Superimpose the four spectra, and determine which solvent is the most effective solvent for extracting chlorophyll from spinach leaves. 

Uses Soil, space, and food fumigant organic synthesis fire extinguishing agent refrigerant disinfestation of potatoes, tomatoes, and other crops solvent for extracting vegetable oils. 

A good solvent for extraction should be selective so that it dissolves the desired analytes to a greater degree than other constituents in the sample matrix. It should be unreactive and stable, preferably nontoxic and from an economic point of view noncorrosive to equipment and inexpensive to buy. Many of these requirements are met by supercritical fluids such as carbon dioxide. 

Uses. Process solvent for extractions of aromatics and for purification of acid gases... 

As an alternative to distillation, extraetion with a eo-solvent that is poorly mis-eible with the ionie liquid has often been used. There are many solvents that can be used to extract product from the ionic liquid phase, whether from a monophase reaction or from a partially miscible system. Typical solvents are alkanes and ethers (15). Supercritical CO2 (SCCO2) was recently shown to be a potential alternative solvent for extraction of organics from ionic liquids (22). CO2 has a remarkably high solubility in ionic liquids. The SCCO2 dissolves quite well in ionic liquids to facilitate extraction, but there is no appreciable ionic liquid solubilization in the CO2 phase in the supercritical state. As a result, pure products can be recovered. For example, about 0.5 mol fraction of CO2 was dissolved at 40°C and 50 bar pressure in [BMIMJPFe, but the total volume was only swelled by 10%. Therefore, supercritical CO2 may be applied to extract a wide variety of solutes from ionic liquids, without product contamination by the ionic liquid (29). 

At trace levels, polonium can be separated effectively by solvent extraction, ion exchange, paper chromatography, and other techniques. Diisopropyl ketone, di-n-octylamine, and tri-n-butylphosphate are suitable solvents for extraction. Trace amounts of polonium in solutions or sohd mixtures containing no other emitters can be determined by measuring its alpha activity. 

Li, Z., Wei, Q., Yuan, R., Zhou, X., Liu, H., Shan, H., and Song, Q., A new room temperature ionic liquid l-butyl-3-trimethylsilylimidazolium hexafluoro-phosphate as a solvent for extraction and preconcentration of mercury with determination by cold vapor atomic absorption spectrometry, Talanta, 71,68-72, 2007. 

The characteristics of an ideal solvent for extraction of lubricating oils may be summarized as follows ... 

Distillation. At different pressures with an added volatile azeotrope-forming substance (for azeotropic distillation) with an added relatively nonvolatile selective solvent (for extractive distillation). 

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