Naphthalene biphenyl mixture

Crystallization without any cleaning step and with thermal sweating is compared with crystallization and following pressure sweating in respect to purity and yield of the product (see Table 1). The effects of N2 and CO2 under different pressures on the crystallization of a p-/m-DCB mixture with 8% m-DCB and a naphthalene/biphenyl mixture with 33% biphenyl are investigated. 

Figure 10.9 shows a plot ofAr against At/AT for the naphthalene-biphenyl mixture. The best straight line drawn through these points had a slope of —0.95 hence x = 0.0175 = 1.75 mole-% contaminant which includes the added biphenyl and the original impurity. From a similar analysis of the naphthalene by itself, x = 0.34 mole-% impurities. Thus, the mole-% biphenyl found experimentally was 1.41 compared to the 1.45 actually added. 

To test this prediction, a solution of o-sulphobenzoic anhydride (0-02 mole) in benzene (0-4 mole) was pyrolyzed at 690°, with a contact time of 18 sec. The pyrolysate, after removal of benzene, weighed 2 2 g. The product mixture, determined by mass spectrometry, is shown in Table 14 together with the products from identical pyrolyses of benzene (35-5 ml) alone (0-3 g product) and of phthalic anhydride (2 96 g 002 mole) in benzene (35-5 ml) (2-6 g product) for comparison. Relative concentrations (vol. %) of the three components for which we have the requisite calibration data (naphthalene biphenyl 3,4-benzocoumarin = 71 100 21) match closely the relative intensities shown in Table 14,... 

The economy of melt crystallization processes depends on the product purity, which is normally increased by an additional cleaning step. The application of gases under pressure is investigated to show possibilities of product quality improvement. Experimental devices for the determination of the freezing curve under gas pressure and for a solid layer crystallization process are shown. The influence of gas and pressure in respect to the freezing curve are explained on the basis of two binary mixtures (trioxane/water and para-/meta-dichlorobenzene) under CO2- and N2- pressure are presented. Furthermore the results of solid layer crystallization experiments with naphthalene/biphenyl and para-/meta-dichlorobenzene mixtures are shown. 

Application of this technique to the identification of methyl esters of the organic acids obtained by the controlled oxidation of bituminous coal allowed the more volatile benzene carboxylic acid esters to be identified (Studier et al., 1978). These were esters of benzene tetracarboxylic acid, tere-phthalic acid, toluic acid, and benzoic acid. Decarboxylation of the total acid mixture was shown to afford benzene, toluene, Cj-benzenes (i.e., ethylbenzene or xylenes), Cj-benzenes, butylbenzenes, Cj-benzenes, Cybenzenes, naphthalene, methylnaphthalene, C2-naphthalene, biphenyl, methylbi-phenyl, C3-biphenyl, indane, methylindane, Cj-indane, phenanthrene, and fluorene. 

Other aryl halides of scientific interest also can be prepared in the laboratory by this method [24-30]. The aromatic group can be alkyl benzene, naphthalene, biphenyl, diphenyl ketone, diphenyl ether, or diphenyl sulfone. The chlorine groups can be ortho, para or the mixture of the two. Some examples are shown by structures (8-10)... 

The retention of 34 nitrated PAH compounds (e.g., quinolines, naphthalenes, biphenyls, anthracenes, fluorenes) was studied on a Cjg column using mobile phases consisting of 50/50, 60/40, and 70/30 mixtures of acetonitrile/water at 35°C, 45 C, 55°C, and 65°C [179]. Aliquots (1 pL) of sanqiles containing 1 mg/mL of each compound were injected. The log K value was tabulated for each compound under each mobile phase/temperature combination. This is an excellent reference for those seeking detailed information on the retention behavior of nitro-PAHs. 

Commercial PCB mixtures frequently contain impurities that may contribute to the 2,3,7,8-TCDD toxic equivalency factor. These impurities may include other PCBs, dioxins, dibenzofurans, naphthalenes, diphenyl ethers and toluenes, phenoxy and biphenyl anisoles, xanthenes, xanthones, anthracenes, and fluorenes (Jones etal. 1993). PCB concentrations in avian tissues sometimes correlate positively with DDE concentrations (Mora et al. 1993). Eggs of peregrine falcons (Falco peregrinus) from California, for example, contained measurable quantities of various organochlorine compounds, including dioxins, dibenzofurans, mirex, hexachlorobenzene, and / ,//-DDE at 7.1 to 26.0 mg/kg FW PCB 126 accounted for 83% of the 2,3,7,8-TCDD equivalents, but its interaction with other detectable organochlorine compounds is largely unknown (Jarman et al. 1993). 

Bioventing technology is applicable to contaminants in the vadose zone as well as contaminated regions just below the water table. It is applicable for any contaminant that degrades more readily aerobically than anaerobically. Most applications have targeted the less volatile petroleum hydrocarbons, although the technology has also remediated mixtures that include acetone, benzene, toluene, biphenyl, phenol, methylphenol, naphthalene, and polycyclic aromatic... 

Electron tunneling between organic species was first detected, by direct kinetic experiments, for reactions of the biphenyl anion radical with naphthalene and pyrene [11] and triphenylethylene [12], As is known, upon irradiating vitreous solutions containing biphenyl or pyrene, Py, these acceptors react with electrons to form Ph2 and Py with characteristic optical spectra [13]. Ph2 particles have been found [11] to enter into the electron exchange reactions at 77 K with naphthalene, Nh, and pyrene molecules in mixtures of ethyl alcohol and diethyl ether (2 1). 

Another classic system - metallic Li and naphthalene (or biphenyl) as electron-carrier - is also prepared in N N.N. N -tetramethylethylenediamine (tmeda) and toluene mixture by US treatment. This system serves for obtaining highly active Rieke metals [708],... 

The major portion of the pyrolysate, apart from 0-62 g of unconverted phthalic anhydride, was 1-05 g of a mixture of naphthalene (15%) and biphenyl (85%). Benzene (100 ml), pyrolyzed under identical conditions, gave no acetylene, and only 0-18 g of high-boiling product, which consisted of about 96% (0-17 g) biphenyl and 4% (0-072 g) terphenyl. Only a trace of naphthalene (about 0-2%, 0-0004 g) was found. 

The data strongly suggest the formation of benzyne from o-sulphobenzoic anhydride—from the products of its reaction with benzene by 1,2- and 1,4-addition (naphthalene, phenylnaphthalene) and insertion (biphenyl, about four times as much by weight as from benzene alone). The uncondensed gases from the reaction were a 1 1 mixture of sulphur dioxide and carbon dioxide. This, in addition to the other products, indicates that the first step of Path 2, loss of sulphur dioxide, is the dominant primary process. However, the resulting zwitterion, unlike its cationic counterpart in the mass spectrometer, does not go on to lose carbon monoxide it stabilizes itself more easily by losing carbon dioxide... 

The photodechlorination of 2,2/,3,3/,6,6/-hexachlorobiphenyl and of three commercial mixtures of polychlorinated biphenyls solubilized in an aqueous solution of poly(sodium styrenesulphonate-co-2-vinylnaphthalene) was studied with the use of solar-simulated radiation426,427. The reaction was found to be photosensitized by the naphthalene antenna units present in the copolymer. Exciplex formation and generation of radical anions lead to dechlorination. 

We have described elsewhere the nature of the MI FTIR spectra of PAHs and their derivatives (1, 12, 13, 1J>, 18, 21-24) the following points are especially significant. First, FTIR spectra devoid of rotational structure and having individual bandwidths on the order of 2-7 cm are obtained both for PAHs and for polar derivatives thereof (such as nitrogen heterocycles) These spectra are sufficiently characteristic to enable identification of individual isomers to be made in mixtures [e.g., the six methylchrysenes (12) and the various mono- and dimethyl naphthalenes and biphenyls (24)]. Second, detection limits for individual PAHs can be as low as 50 ng, if special "micro samp ling 1 deposition apparatus is used (23) Third, Beer s law plots typically are linear over 1.5-2 decades in PAH concentration by the complementary use of two different deposition cells, linearity over 3 decades in PAH concentration for Beer s law plots can be approached (23). Finally, for both MI FTIR and MI fluorescence spectrometry, analytical precision of ca. 3-7 % relative standard deviation can be achieved. 

Figure 8 Plot of electroosmotic flow velocity against temperature. Column, 50 pm x 21/29-cm capillary packed with 5-pm Spherisorb ODS 300 A eluent, 10 mM Na-phosphate in 2 3 water ACN mixture (v/v) samples, ( ) benzaldehyde, ( ) naphthalene, (A) biphenyl, (O) fluorene, and ( ) /r>terphenyl. (Reprinted from Ref. 42, copyright 1999, with permission from Elsevier Science.)...

The most typical example of a radical anion-electrophile combination is the carboxylation of aromatics (Scheme 3 naphthalene [28], phenanthrene, anthracene, pyrene [29] cyclopenta[de/]phenanthrene [30] and, with lower yield, biphenyl [31]) with C02 by irradiation in the presence of donors such as amines or p-dimethoxybenzene (pDMB). A mixture of dihydro derivatives and rearomatized products is usually obtained. 

Assume that an impurity is added to the equilibrium mixture of pure solid and liquid naphthalene. Assume further that this impurity is biphenyl, which is soluble in liquid but not solid naphthalene. The vapor pressure of the liquid is lowered. Consequently the... 

The electric arc between titanium electrodes submerged in methanol was conducted according to the standard method given in Section 8.2.1. After 10 min arcing the polyyne solution obtained was filtered and injected into the HPLC-DAD column for analysis. The formation of carbon derived from the carbonization of the solvent was much less significant than in the previous experiment carried out in -hexane. In this case, no polyynes were detected even in trace amounts by HPLC analysis. Only a mixture of about 12 PAHs was obtained. Among them biphenyl, naphthalene, acenaphtha-lene, phenanthrene, anthracene, perylene, and fluoranthene were identified. 

Optically active l-halo-l-mefhyl-2,2-diphenylcyclopropanes 61 are used as probes to investigate the mechanisms of calcium reduction [39]. Treatment of 61 with calcium biphenyl (Ca(BPh)2) or calcium naphthalene (Ca(NPh)2) then addition of CO2 gives a mixture of cyclopropane derivative 62 and the corresponding carboxylic acid 63 (Scheme 4.17). Walborsky and Hamdouchi have provided evidence showing that these reactions occur by single electron transfer to yield free radicals... 

The photolytic removal of chlorine from chlorobenzene, chlorophenols and chlorinated biphenyls and dioxins continues to be examined as a potential solution to the problem of the destruction of these compounds when present as environmental pollutants. Guillet has reported that aqueous solutions of the copolymer of vinyl-naphthalene and styrene sulphonate will solubilize to a small degree 2,2, 3,3, 6,6 -hexachlorobiphenyl, and that illumination of the solution with simulated sunlight leads to the formation of biphenyls with fewer chlorine substituents. It is suggested that the process involves the absorption of light by the naphthalene and exciplex formation with the biphenyl followed by electron transfer to the biphenyl. The chlorinated biphenyl anion radical would then be expected to expel chloride ion. The dechlorination of mixtures of variously chlorinated biphenyls (such as those typically used as... 

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