Chlorinated compound solvent

Although the product indicated satisfactory removal of the chlorinated solvent, the product specification proposed by the client excluded the use or presence of chlorinated compounds. Solvent use would have provided us with more controlled conditions, allowed us to recycle most of the material, and provided reasonable throughput. Very few solvents have a boiling-point range of 75 to 85°C and are inert to nitric acid. The search for an inert substitute for EDC suitable in this boiling-point range was not successful. An alternative solution would be to run the reaction without the use of solvent. 

Chisolm s Law See problem and solution, chlorinated compound solvent A solvent that confers low-flammability properties in comparison with other types of solvents. It is used where fire hazards are a matter of importance. See fire solvent. 

Textiles Metals, pigments, organic chlorine compounds, solvents... 

Chemical Properties. A combination of excellent chemical and mechanical properties at elevated temperatures result in high performance service in the chemical processing industry. Teflon PEA resins have been exposed to a variety of organic and inorganic compounds commonly encountered in chemical service (26). They are not attacked by inorganic acids, bases, halogens, metal salt solutions, organic acids, and anhydrides. Aromatic and ahphatic hydrocarbons, alcohols, aldehydes, ketones, ethers, amines, esters, chlorinated compounds, and other polymer solvents have Httle effect. However, like other perfluorinated polymers,they react with alkah metals and elemental fluorine. 

Methylene chloride is one of the more stable of the chlorinated hydrocarbon solvents. Its initial thermal degradation temperature is 120°C in dry air (1). This temperature decreases as the moisture content increases. The reaction produces mainly HCl with trace amounts of phosgene. Decomposition under these conditions can be inhibited by the addition of small quantities (0.0001—1.0%) of phenoHc compounds, eg, phenol, hydroquinone, -cresol, resorcinol, thymol, and 1-naphthol (2). Stabilization may also be effected by the addition of small amounts of amines (3) or a mixture of nitromethane and 1,4-dioxane. The latter diminishes attack on aluminum and inhibits kon-catalyzed reactions of methylene chloride (4). The addition of small amounts of epoxides can also inhibit aluminum reactions catalyzed by iron (5). On prolonged contact with water, methylene chloride hydrolyzes very slowly, forming HCl as the primary product. On prolonged heating with water in a sealed vessel at 140—170°C, methylene chloride yields formaldehyde and hydrochloric acid as shown by the following equation (6). 

Solvents. NBRs are soluble in aromatic hydrocarbons, chlorinated hydrocarbons, ketones, esters and nitroparaffin compounds. Solvents with high evaporation rate are acetone, methyl ethyl ketone, chloroform and ethyl acetate, among others. Solvents with slow evaporation rate are nitromethane, dichloropentenes, chloro-toluene, butyl acetate and methyl isobutyl ketone. 

Ketones, chlorinated compounds Organic solvents, acids... 

In addition to being the most widely used disinfectant for water treatment, chlorine is extensively used in a variety of products, including paper products, dyestuffs, textiles, petroleum products, pharmaceuticals, antiseptics, insecticides, foodstuffs, solvents, paints, and other consumer products. Most chlorine produced is used in the manufacture of chlorinated compounds for sanitation, pulp bleaching, disinfectants, and textile processing. It is also used in the manufacture of chlorates, chloroform, and carbon tetrachloride and in the extraction of bromine. Among other past uses, chlorine served as a war gas during World War I. 

This has the same stiffness as dry nylon but absorbs less than one-fifth the amount of water and retains its strength and shape in humid conditions at considerably higher temperatures. Acetal has poor resistance to aqueous solutions of strong acids and should not be used at a pH below 3. The acetal s copolymers are satisfactory in most alkaline conditions. All grades have very good resistance to mineral oils and petrols and to most organic solvents including chlorinated compounds. 

Protocol for assessing the performance of a diffusive sampler Chlorinated hydrocarbon solvent vapours in air Beryllium and inorganic compounds of beryllium in air... 

Particularly the chlorinated compounds have enjoyed range of applications vinyl chloride (chloro-ethene) as monomer for the production of PVC, tetra- and trichloroethenes as solvents for degreasing, and the insecticides l,l,l-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and isomers of hexachlorocyclohexane (HCH) (benzene hexachloride). The biodegradation of fluorinated aliphatic compounds is generally different from the outlines that have emerged from investigations on their chlorinated, brominated, and even iodinated analogues. They are therefore treated separately in Part 4 of this chapter. 

Solvent-assisted decaffeination of coffee can result in residues of solvent reaching the consumer.208 The use of chlorinated hydrocarbon solvents such as chloroform,209 methylene chloride, trichloroethylene,208 and difluoromonochloromethane (Freon),210 will probably be replaced by compounds already found in roasted coffee. The use of an ethyl acetate and 2-butanone mixture leaves a 26-ppm residue in green coffee, but zero residue in roasted coffee.211 Other solvent compounds used or suggested for coffee improvement or decaffeination include propane, butane,212 carbon dioxide,213 214 acetone215 dimethyl succinate,2161,1-dimethoxymethane, and 1,1-dimethoxyethane.217 Of all these, supercritical carbon dioxide, ethyl acetate, and methylene chloride are the solvents most used currently in decaffeination processes. 

Pyrrolidones fit well into the bio-refinery concept since they may be produced in a scheme beginning with the fermentation of a portion of the bio-refineiy s sugar product into succinate. Pyrrolidones are a class of industrially important chemicals with a variety of uses including polymer intermediates, cleaners, and green solvents which can replace hazardous chlorinated compounds. 

Amaral OC, Otero R, Grimalt JO, Albaiges J (1996) Volatile and semi-volatile organochlorine compounds in tap and riverine waters in the area of influence of a chlorinated organic solvent factory. Water Res 30(8) 1876-1884... 

In interpreting the data for the total petroleum hydrocarbons in a sample, the amount of moisture cannot be ignored because moistme blocks the extraction of petroleum hydrocarbons by another hydrocarbon (Freon). Potentially, sulfm or phthalate compounds also interfere with total petroleum hydrocarbons analyses. This is similar to the problem of strong interferences from phthalate esters or chlorinated solvents when one is using electron capture methods to look for chlorinated compounds such as polycholorbiphenyls or pesticides. 

Miscible with alcohol, ether, benzene (Windholz et ah, 1983), and many other organic solvents, particularly chlorinated compounds (e.g., carbon tetrachloride, methylene chloride, chloroform,... 

Source Hexachlorobenzene may enter the environment from incomplete combustion of chlorinated compounds including mirex, kepone, chlorobenzenes, pentachlorophenol, PVC, polychlorinated biphenyls, and chlorinated solvents (Ahling et al., 1978 Dellinger et al., 1991). In addition, hexachlorobenzene may enter the environment as a reaction by-product in the production of carbon tetrachloride, dichloroethylene, hexachlorobutadiene, trichloroethylene, tetrachloro-ethylene, pentachloronitrobenzene, and vinyl chloride monomer (quoted, Verschueren, 1983). 

Chlorine isotope studies have been applied to understand the environmental chemistry of anthropogenic organic compounds, such as chlorinated organic solvents or biphenyls. The primary goal of such studies is to identify and quantify sources and... 

Uses. 1,2-Dichloroethylene is used as a solvent for organic materials and as an intermediate in the synthesis of other chlorinated compounds it may be produced by the chlorination of acetylene but is often produced as a by-product in the manufacture of other chlorinated compounds. 

BioSparge is typically ineffective in silts and clays where the porosity and permeability are low. Also, remediation of certain semivolatile compounds, including chlorinated solvents, requires that the system be modified by the addition of an ozone generator. The ozone reacts with the chlorinated compounds to produce by-products that can be biodegraded. 

The formation of chloro compounds in related reactions in chlorine-containing solvents had been observed before, and was attributed to reaction of the car-bonium ion with solvent.219 20... 

Liang, L-N. Grbif-Galif, D. (1993). Biotransformation of chlorinated aliphatic solvents in the presence of aromatic compounds under methanogenic conditions. Environmental Toxicology and Chemistry, 12, 1377-93. 

Nontoxic fluorinated hydrocarbons were probably some of the earliest and are even now the most often used solvents for lab-scale applications, mainly in the ozonation of chlorinated compounds (Stich et al., 1987 Bhattacharyya et al 1995 Guha et a]., 1995 Freshour et al., 1996 Shanbhag et al., 1996). 

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