Solvent, solvents perchloroethylene

The solvent perchloroethylene (PERC) is used by approximately 90% of all EU dry cleaners today. ... 

In our second example we consider the reduction of chlorinated ethenes including the prominent solvents tetrachloroethene (perchloroethylene, PCE) and trichloro-ethene (TCE). An overview of the hypothesized reaction sequence for reduction of these compounds by zero-valent iron (Fe(0) has been constructed (Fig. 14.15 Arnold and Roberts, 2000). Identical or very similar reaction schemes have been... 

An interesting property of resins impregnated with oximes or oxines is that the selectivity of, for example, copper over iron(III), approaches that of a pure solvent-extraction process only when an inert solvent is present in the pores of the resin.396 Thus, in a /S-hydroxyoxime SIR, the selectivity for copper over iron(III) improved by a factor of 20 when the solvent perchloroethylene was introduced into the SIR, and by a factor of 700 in a similar resin impregnated with 8-hydroxy-quinoline.396 This is believed to be due to kinetic and thermodynamic restrictions in the extraction of iron(III), but not of copper, at an aqueous—organic boundary.396 397... 

Dry cleaners remove oil and grease spots from clothing by using an organic solvent called perchloroethylene. What separation technique do the cleaners use ... 

The dry cleaning industry is one of the largest consumers of solvents. Perchloroethylene (PCE) is used in as high as 80% of the dry cleaning applications. Although this solvent is nonflammable, easy to recover, and exhibits good solvency, its environmental impact is severe. There is work underway to reduce the emission of this solvent from the dry cleaning plants. 

OTHER COMMENTS use as an oil and fat solvent solvent in plastics, resins, and metals industries used in dry cleaning fluids and degreasing intermediate for perchloroethylene and carbon tetrachloride used in insecticidal fumigant mixtures. 

JP has been calciflated for 16 current-use pesticides [8], the surfactant nonylphenol polyethoxylate (NPnEO), and the solvent perchloroethylene [5], based on a thorough compilation of experimental data on compound properties and transformation schemes (if such data are not available, they have to be estimated as described in Sect. 4.2). hi Fig. 2, the JP results for the 18 compounds are displayed. 

Fig. 2 Primary (PP) and joint persistence (JP) for 16 pesticides, the surfactant nonylphe-nol polyethoxylate (NPnEO), and the solvent perchloroethylene sorted according to JP. The dashed line indicates the 60-day water half-life used as persistence criterion in the Stockholm Convention [25]. Reprinted with permission from [8], p 2447. (2007) American Chemical Society...

Hara M, Kino M, Yamamoto et al. 1985. Cardiovascular effects of organic solvents (perchloroethylene) (PERC). JpnCirc 149 887-888. 

Solvents at or near room temperature would be expected to produce pain and transient irritation when splashed into the eye and promptly flushed with water. Hot solvent, particularly perchloroethylene... 

Of all the normally used solvents, perchloroethylene has the highest density. It is therefore the most likely to cause problems in the overloading of pump motors and structures carrying storage vessels. If recovery is proposed on a general-purpose plant, a careful survey of the effect that excess density may have must be made. A pallet of 4 X 200 litre drums will weigh almost 1.5 Te. 

Many of the cleaning applications which formally used 1,1,1-trichloro-ethane (1,1,1-Tri) or 1,1,2-trichlorotrifluoroethane (CFC 113) are using methylene chloride, trichloroethylene, and perchloroethylene as substitute solvents. Solvent blends that have solvency similar to 1,1,1-Tri and CFC 113 and which contain several halogenated solvents have been introduced by the OxyChem division of Occidental Chemical Corporation. These blends sold under the trademark of Oxsol are solvents with varying evaporation rates and solvency. Components of these blends include monochlorotoluene, perchloroethylene, p-chlorobenzotrifluoride, and 3,4-dichlorobenzotrifluoride. These patented formulations will be discussed later in the section on solvent properties. 

Worker safety issues are important when handling any organic solvent. Written procedures that follow the MSDS guidelines are recommended for all workers who handle any of the halogenated solvents. Workers must remember that some of the halogenated solvents have flash points as listed in the physical property tables. All of the solvents except perchloroethylene have a limited... 

Useful with Solvents Perchloroethylene, Hydrocarbons, Glycols Si Glycol Ethers, any high-bolling solvent Any... 

But the secondary demand for cooling cannot be fulfilled with CTW. The reason is that it is not cold enough to condense any solvent (including perchloroethylene) such that air emitted at the top of the degreaser is adequately free of contamination. Refrigerated brine is necessary for the secondary cooling coil. 

Common solvents - toluene, perchloroethylene, carbon tetrachloride, carbon disufide, MEK, dioxane, cyclohexanone, ethyl acetate ... 

Pennyweight A unit of weight in the Troy (t) weight system equal to 24 grains or 1.555 grams. Perchloroethylene (perc) (cleaning) The solvent perchloroethylene (CCI2CCI2). 

Chlorinated Solvents. Originally, successive chlorination and dehydro-chlorination of acetylene was the route to trichloroethylene [79-01-6], C2HCI3, and perchloroethylene [127-18-4], C2C1. ... 

Halogenation and Hydrohalogenation. Halogens add to the triple bond of acetylene. FeCl catalyzes the addition of CI2 to acetylene to form 1,1,2,2-tetrachloroethane which is an intermediate in the production of the industrial solvents 1,2-dichloroethylene, trichloroethylene, and perchloroethylene (see Chlorocarbons and chlorohydrocarbons). Acetylene can be chlorinated to 1,2-dichloroethylene directiy using FeCl as a catalyst... 

Chlorination of various hydrocarbon feedstocks produces many usehil chlorinated solvents, intermediates, and chemical products. The chlorinated derivatives provide a primary method of upgrading the value of industrial chlorine. The principal chlorinated hydrocarbons produced industrially include chloromethane (methyl chloride), dichloromethane (methylene chloride), trichloromethane (chloroform), tetrachloromethane (carbon tetrachloride), chloroethene (vinyl chloride monomer, VCM), 1,1-dichloroethene (vinylidene chloride), 1,1,2-trichloroethene (trichloroethylene), 1,1,2,2-tetrachloroethene (perchloroethylene), mono- and dichloroben2enes, 1,1,1-trichloroethane (methyl chloroform), 1,1,2-trichloroethane, and 1,2-dichloroethane (ethylene dichloride [540-59-0], EDC). 

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