With organic solvents

C HjCla, PhCCla. Colourless liquid, b.p. 2I3-214" C. Insoluble in water, miscible with organic solvents. 

Base, neutral, and acid compounds, which may be less volatile, are extracted from the matrix with organic solvents. 

Isophorone. Isophorone (3,5,5-trimethyl-2-cyclohexen-l-one) is a cycHc a,P-unsaturated ketone derived from the trimeri2ation of acetone. It has a light yellow color and a disagreeable camphoraceous odor. It has the tendency to discolor and form residues on prolonged storage. Isophorone is completely miscible with organic solvents, and other physical properties are Hsted ia Table 1. 

Penta.nedione, 2,4-Pentanedione [123-54-6] (acetylacetone) is the lowest member of the aUphatic 1,3-diketones and is a colorless Hquid with a mild ketone-like odor. It is completely miscible with organic solvents other physical properties ate shown in Table 1. 

Latexes of synthetic resins are identified by ir spectrometry. Selective extraction with organic solvents is used to obtain purified fractions of the polymers for spectrometric identification. Polymeric films can be identified by the multiple internal reflectance ir technique, if the film is smooth enough to permit intimate contact with the reflectance plate. TAPPI and ASTM procedures have not been written for these instmmental methods, because the interpretation of spectra is not amenable to standardization. 

In general, all iron pigments are characteri2ed by low chroma and excellent Hghtfastness. They are nontoxic, nonbleeding, and inexpensive. They do not react with weak acids and alkaHes, and if they are not contaminated with manganese, do not react with organic solvents. However, properties vary from one oxide to another. 

Contamination by water-insoluble reaction by-products such as l-amino-2,4-dibromoanthraquinone affects the quaUty of dyestuff signiftcandy. Therefore, several methods for purification have been reported. Examples are extraction of impurities with organic solvent (18), or precipitation of bromamine acid from concentrated (60—85%) sulfuric acid (26). 

A monoacetate can be isolated by continuous extraction with organic solvents such as cyclohexane/CCl4. 

Water-soluble salts are best purified by preparing a concentrated aqueous solution to which, after decolorising with charcoal and filtering, ethanol or acetone is added so that the salts crystallise. They are collected, washed with aqueous ethanol or aqueous acetone, and dried. In some cases, water-soluble salts can be recrystallised satisfactorily from alcohols. Water-insoluble salts are purified by Soxhlet extraction, first with organic solvents and then with water, to remove soluble contaminants. The purified salt is recovered from the thimble. 

Greater success has been achieved with organic solvents which are also hydrohalide acceptors, pyridine being a specific example. 

Perchloroethylene is a clear, dense, non-flammable volatile chlorinated solvent. It is widely used for dry cleaning small quantities are used in adhesives and cleaning agents. It is miscible with organic solvents but only slightly soluble in water. Relevant physical properties are given in Table 5.50. 

In densely populated areas, traffic is responsible for massive exhausts of nitrous oxides, soot, polyaromatic hydrocarbons, and carbon monoxide. Traffic emissions also markedly contribute to the formation of ozone in the lower parts of the atmosphere. In large cities, fine particle exposure causes excess mortality which varies between one and five percent in the general population. Contamination of the ground water reservoirs with organic solvents has caused concern in many countries due to the persistent nature of the pollution. A total exposure assessment that takes into consideration all exposures via all routes is a relatively new concept, the significance of which is rapidly increasing. 

Grace and Co.) is added to the mixture which is refluxed for 5-10 min or until the gas evolution is complete. The product, often an aziridine, is obtained by pouring the reaction mixture into water and either by filtering or by extracting the precipitate with organic solvent followed by a water wash and drying. 

Nonionic hydrophobic Polyvinylpyrrolidone Buffer or salt solution with organic solvent (e.g., 20% CH,CN in 0.1 M NaNOd... 

For the size exclusion chromatography of proteins on silica-hased diol packings, it is generally recommended to use fully aqueous mobile phases with a salt concentration between 0.1 and 0.3 M. In general, a phosphate buffer around pH 7 is used as the mobile phase. Under these circumstances, the tertiary structure of most proteins is preserved without difficulty and the interaction of proteins with each other is minimized. However, other inorganic buffers or combinations of buffers with organic solvents can be used without difficulties for special applications. 

A monoacetate can be isolated by continuous extraction with organic solvents such as cyclohexane/CCI4. Monoacylation can also be achieved by ion exchange resin or acid-catalyzed transesterification. 

Complexing extraction of pyridine bases from coal coking products with organic solvents 97KGS3. 

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