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Industrial solvents ethyl benzene

Of all the food categories, dairy products also contain one of the higher frequencies of industrial chemicals (see Exhibit 2). This is expected because these industrial chemicals tend to accumulate in the fat of dairy products. The diversity of the chemicals found in dairy products, however, occurs for several reasons. Because chloroform is a byproduct of using a chlorine disinfectant, it would appear that a significant number of dairy producers in the United States either do not rinse or do not completely rinse their equipment after disinfection2. Another source of disinfection byproducts is from water that may be used in a dairy. Benzene, toluene, ethyl benzene, and xylenes and the other detected chlorinated petroleum solvents (e.g., CBZ, DCE, PCE, TCA, and TCE) occur in dairy foods is because (1) these chemicals were in products used to lubricate or clean machinery that contacted the dairy products or (2) these chemicals were in the ambient air of the dairy. [Pg.23]

Snyder CA. 1987. Benzene. In Snyder R, ed. Ethyl Browning s toxicity and metabolism of industrial solvents, 2nd ed., Vol. 1 Hydrocarbons. [Pg.415]

Ethyl benzene is used as an industrial solvent, and as a component in automotive and aviation fuels. The majority of ethyl benzene is used in the production of styrene. [Pg.1093]

Among the xylene isomers p-xylene is commercially the most important and highest volume chemical because p-xylene is the critical feed stock for production of purified ter-ephthalic acid or dimethyl terephthalate which is converted to synthetic fibers. O-xylene is the next important isomer which is used for manufacture of phthalic anhydride. M-xylene is commercially the least important isomer and more often than not it is not separated as a pure product and is sold as a component of mixed xylenes along with ethyl benzene as a solvent or as a thinning agent in the paint industry. [Pg.7]

Some industrial solvents are found on the Proposition 65 list. As of January 1, 1993 (2), benzene, carbon tetrachloride, chloroform, methylene chloride, 1,4-dioxane, 2-nitropropane, and perchloroethylene have been listed as substances known to the state of California to cause cancer. Ethyl alcohol in alcoholic beverages, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, and toluene are listed as substances known to the state of California to cause reproductive toxicity. Because the list is being expanded periodically, it is necessary for a user of industrial solvents to maintain awareness of the Proposition 65 list. [Pg.263]

Alcohol, denatured n. Ethyl alcohol that has been adulterated with a toxic material such as acetaldehyde or benzene so as to render it unfit for human consumption but still useful as an industrial solvent or, occasionally, as a reactant. [Pg.36]

Nowadays, the most commonly used solvents are mineral or white spirits. Aromatic hydrocarbon solvents, such as xylene and toluene, are used in certain specialized industrial paints. Other solvents include a wide variety of alcohols (isobutanol, i-butanol), esters (ethyl acetate, butyl or isobutylacetate) and ketones (acetone, methyl ethyl ketone). Often, a mixture of different solvents is used to ensure the desired outcome, e.g., in thinners (Mathias 1984 Valsecchi et al. 1992 Rose and Vance 1997 Leira 1997). In Scandinavia, there has been a tendency for more than a decade to reduce the use of the more toxic solvents, including benzene, n-hexane and the chlorinated solvents, particularly carbon tetrachloride, chloroform, dichloroethane and trichloroethylene (Leira 1997). [Pg.668]

The range and parity of solvents have improved considerably over recent centuries. At the beginning of the twentieth century, it was difficult (and expensive) to obtain acetone without water or toluene without sulphur contamination (Thorpe, 1913). These contaminants would have short- and long-term effects on objects and would create different behaviours to that expected now of nominally the same materials. All solvents contain impurities. Solvents bought as chani-cals can be obtained at very high purity, up to 99.999% for critical applications such as pesticide analysis. For many industrial purposes, high purity (>95%) is not necessary. However, the purity of solvents used on objects should be at least 99%, and there should not be any non-volatile impurities or any that might react with or remain in the object (Khanjian et al., 2004). Many solvents are not sold as pure chemicals but to conform with performance specifications, particularly ethanol and hydrocarbon solvents. For instance, specifications for Xylene S do not explicitly state that xylene is present (Shell, 2007) and commercial xylene often contains ethyl benzene as part of the mixture. [Pg.95]

As shown by reaction 8.5.2.1, in the homogeneous catalytic process r-butyl hydroperoxide is reacted with propylene in the first step to give PO and f-butanol. Tertiary butyl hydroperoxide is made by the oxidation of neopentane. Alternatively, ethyl benzene can be converted to its hydroperoxide and then reacted with propylene. Industrially, oxidations of neopentane or ethyl benzene to the corresponding hydroperoxides are performed using air. These oxidations are carried out in the absence of solvents and a catalyst. [Pg.256]

The solvent employed in the first commercial installation, of the Indian Refining Co., was a mixture of acetone and benzene (90% grade). In the subsequent development of the process by The Texas Co., a large number of solvents were found to be satisfactory. At present, the process normally employs a mixture of methyl ethyl ketone and industrial grade benzene, which have been found to be admirably suitable and provide a relatively low cost solvent. Toluene is substituted for all or part of the benzene when low chilling temperatures are required to obtain oils of very low pour point, as benzene may crystallize out from the mixture at these lower temperatures. [Pg.167]

One of the major uses of activated carbon is in the recovery of solvents from industrial process effluents. Dry cleaning, paints, adhesives, polymer manufacturing, and printing are some examples. Since, as a result of the highly volatile character of many solvents, they cannot be emitted directly into the atmosphere. Typical solvents recovered by active carbon are acetone, benzene, ethanol, ethyl ether, pentane, methylene chloride, tetrahydrofuran, toluene, xylene, chlorinated hydrocarbons, and other aromatic compounds [78], Besides, automotive emissions make a large contribution to urban and global air pollution. Some VOCs and other air contaminants are emitted by automobiles through the exhaust system and also by the fuel system, and activated carbons are used to control these emissions [77,78],... [Pg.320]

OTHER COMMENTS coal tar naphtha is a mixture of aromatic hydrocarbons, mainly toluene, xylene, and cumene however, those coal tar naphthas with low boiling points contain appreciable amounts of benzene used as a diluent in coatings, inks, paints, resins, and cements used in the preparation of coumarone and indene utilized as a solvent in the rubber industry utilized in formulations of nitrocellulose and ethyl cellulose. [Pg.765]

In attempts to overcome the limitations of aqueous phase enzymatic reactions, organic media such as ethyl acetate, cyclohexane, and benzene are being tried as solvents. An industrially viable application of this variation is the lipase-catalyzed preparation of (R)-glycidyl butyrate (1), used in the production of (S)-(S)-/3-blockers (2) (Ladner and Whitesides, 1984),... [Pg.257]

Tables 14.13.1 and 14.13.2 give information on the reported solvent releases and transfers from the iron and steel industries. Not all the solvents listed in the tables are used in processing. Some are by-products of coke manufacture from coal. Benzene and polycyclic aromatics compounds are by-products. Strong solvents such as methyl ethyl ketone, toluene, xylene, and trichloroethylene are typical of those used in cleaning processes. There is no program formulated by the industry to reduce amounts of solvents used. Tables 14.13.1 and 14.13.2 give information on the reported solvent releases and transfers from the iron and steel industries. Not all the solvents listed in the tables are used in processing. Some are by-products of coke manufacture from coal. Benzene and polycyclic aromatics compounds are by-products. Strong solvents such as methyl ethyl ketone, toluene, xylene, and trichloroethylene are typical of those used in cleaning processes. There is no program formulated by the industry to reduce amounts of solvents used.
Stability. In the food industry, where steam sterilisation is required, PES is used instead of PS. Among the newer membranes in use are polyimide (PI) polymeric membranes. Poly-imide UF membranes are promising because of their resistance to many organic solvents [32] such as hexane, benzene, methanol, acetic acid, acetone, ethyl ether, ethoxy ethanol and chlorinated hydrocarbons. [Pg.37]


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See also in sourсe #XX -- [ Pg.542 ]




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