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Naphthalene, combustion

No source of environmental RPCNs other than chlorination in bleaching-related processes is known. Analysis of urban air of Bordeaux showed abundant occurrence of methyl, dimethyl, and trimethyl naphthalenes (obvious oil components) and also mono- and dichloro naphthalenes (combustion products), but no traces of RPCNs [46]. [Pg.12]

To illustrate the effect of basis set selection, we show in Table 2 the reaction energy for naphthalene combustion in the gas phase ... [Pg.103]

Table 2 Single-Point Calculations (with the PBE/TZVP/RI Geometry) Using PBE Functional for Reaction Energy for Naphthalene Combustion... Table 2 Single-Point Calculations (with the PBE/TZVP/RI Geometry) Using PBE Functional for Reaction Energy for Naphthalene Combustion...
The unit Kureha operated at Nakoso to process 120,000 metric tons per year of naphtha produces a mix of acetylene and ethylene at a 1 1 ratio. Kureha s development work was directed toward producing ethylene from cmde oil. Their work showed that at extreme operating conditions, 2000°C and short residence time, appreciable acetylene production was possible. In the process, cmde oil or naphtha is sprayed with superheated steam into the specially designed reactor. The steam is superheated to 2000°C in refractory lined, pebble bed regenerative-type heaters. A pair of the heaters are used with countercurrent flows of combustion gas and steam to alternately heat the refractory and produce the superheated steam. In addition to the acetylene and ethylene products, the process produces a variety of by-products including pitch, tars, and oils rich in naphthalene. One of the important attributes of this type of reactor is its abiUty to produce variable quantities of ethylene as a coproduct by dropping the reaction temperature (20—22). [Pg.390]

K chlorate and aromatic hydrocarbons (such as naphthalene), and not more than 12% nitro-hydrocarbons (but no trinitro compds), the remainder consisting of paraffins, fatty oils, flour or other combustibles. It might also contain not more than 4% blasting gelatin. The prefixes Gesteins- and Wetter- were applied if the expls were intended for rock or coal mine use Ref Marshall, Diet (1920), 65... [Pg.199]

Addition Products of Naphthalene The measurements of heats of combustion made by Roth and Auwers4 show that liquid... [Pg.142]

The flash point represents the minimum temperature at which an ignitable mixture exists above a liquid surface. By definition, flash points are inapplicable to gases. Some solids, e.g. naphthalene and camphor, are easily volatilized on heating so that flammable mixtures develop above the solid surface and hence flash points can be determined. (However, although these substances can be ignited, they generally need to be heated above their flash points in order for combustion to be sustained this is the fire point .)... [Pg.107]

Considerable attention has been directed to the formation of nitroarenes that may be formed by several mechanisms (a) initial reaction with hydroxyl radicals followed by reactions with nitrate radicals or NO2 and (b) direct reaction with nitrate radicals. The first is important for arenes in the troposphere, whereas the second is a thermal reaction that occurs during combustion of arenes. The kinetics of formation of nitroarenes by gas-phase reaction with N2O5 has been examined for naphthalene (Pitts et al. 1985a) and methylnaphthalenes (Zielinska et al. 1989) biphenyl (Atkinson et al. 1987b,c) acephenanthrylene (Zielinska et al. 1988) and for adsorbed pyrene (Pitts et al. 1985b). Both... [Pg.20]

There is considerable variation in the heat of reaction data employed in different articles in the literature that deals with this reaction. Cited values differ by more than an order of magnitude. If we utilize heat of combustion data for naphthalene and phthalic anhydride and correct for the fact that water will be a gas instead of a liquid at the conditions of interest, we find that for the first reaction (equation 13.2.3) the standard enthalpy change will be approximately — 429 kcal/g mole for the second reaction it will be approximately — 760 kcal/g mole. These values will be used as appropriate for the temperature range of interest. Any variation of these parameters with temperature may be neglected. [Pg.558]

Naphthalene was detected in soot generated from underventilated combustion of natural gas doped with toluene (3 mole %) (Tolocka and Miller, 1995). [Pg.827]

Schauer et al. (2001) measured organic compound emission rates for volatile organic compounds, gas-phase semi-volatile organic compounds, and particle-phase organic compounds from the residential (fireplace) combustion of pine, oak, and eucalyptus. The gas-phase emission rate of naphthalene was 227 mg/kg of pine burned. Emission rates of naphthalene were not measured during the combustion of oak and eucalyptus. [Pg.827]

All organic chemicals are essentially combustible. Combustion of some chemicals, such as sulfur and sulfides of sodium, potassium, and phosphorous, result in the production of hazardous gases, in this case sulfur dioxide. Carbon black, lamp black, lead sulfocyanate, nitroaniline, nitrochlorobenze, and naphthalene are examples of combustible chemicals. [Pg.410]

The strain of 1 has been determined experimentally from silver-ion catalyzed methanolysis to be ca. 68 kcal/mol, and that of cyclopropa[/j]naphthalene to be 65-67 kcal/mol. Combustion calorimetry gave a value of 67.8 kcal/mol. For dicyclopropa[/>,g]naphthalene (115) a lower limit of 166 kcal/mol was found. These energies are well reproduced by ab initio, and even by semiempirical calculations. Thus 3-2IG calculates a strain energy of 70 kcal/mol while 3-2IG gives 71.6. At the MP2/6-31G level the strain of 1 is 71.3 kcal/mol, while that of cyclopropene amounts to 57.4 kcal/mol. This latter value compares well with the experimental one, which is 52.6 kcal/mol. While semiempirical calculations have been found unreliable for cycloproparene structures, the calculated strain energies are usually close to reality for MINDO/3, MNDO, and force-field-SCF calculations. The strain energies of the dicyclopropabenzenes (100, 102) have been predicted to be 133 and 140 kcal/mol, respectively, and that of tricyclo-propabenzene (260) to be 217 kcal/mol (3-21G). ... [Pg.73]

These simple molecular orbital pictures provide useful descriptions of the structures and spectroscopic properties of planar conjugated molecules such as benzene and naphthalene, and heterocychc species such as pyridine. Heats of combustion or hydrogenation reflect the resonance stabilization of the ground states of these systems. Spectroscopic properties in the visible and near-ultraviolet depend on the nature and distribution of low-lying excited electronic states. The success of the simple molecular orbital description in rationalizing these experimental data speaks for the importance of symmetry in determining the basic characteristics of the molecular energy levels. [Pg.103]

Numerous polymers autooxidize to form peroxides. These compositionally, and thus calorimetrically, ill-defined products may be considered polymeric peroxides. However, one well-defined polymeric peroxide is that of polystyrene with the repeat unit —CHa-CH(CeH5)-0-0-. Through a combination of combustion and reaction calorimetry (chain degradation to benzaldehyde and formaldehyde), a solid phase enthalpy of formation of this species was found to be 27 21 kJ mol . Much the same procedure was used to determine the enthalpy of degradation for the polyperoxide polymers of 2-vinylnaphthalene and the isomeric 1- and 2-propenylnaphthalene to form the related acylnaphthalene and formaldehyde. Numerically, the reaction enthalpy values for these last three polyperoxides were —206+4, —222 + 8 and —222 + 10 kJmol, to be compared with the aforementioned polystyrene with a value of —209 + 8 kJ mol. However, in the absence of enthalpy of formation data for the decomposition products in the naphthalene case, we hesitate to derive enthalpies of formation for these three species. ... [Pg.155]

Automotive gasoline is essentially a blend of hydrocarbons derived from petroleum and is used to fuel internal combustion, spark-ignition engines. Gasoline contains hundreds of individual hydrocarbons which range from n-butane to Cn hydrocarbons such as methyl naphthalene. [Pg.39]

In a laboratory environmental chamber study of the gas-phase photooxidation of naphthalene and phenan-threne, Sasaki and co-workers (1997b) found two products, 2-nitronaphthalene and 2-nitrodibenzopyranone (XI), that displayed significant genotoxicity in the MCL-5 human cell assay. This finding emphasized the importance of atmospheric reactions in forming mutagens, since the concentrations of such compounds are relatively high in ambient air compared to those expected for nitroarenes directly emitted from primary combustion sources (see Section F). [Pg.484]

Problem 10.12 Draw a conclusion about the stability and aromaticity of naphthalene from the fact that the experimentally determined heat of combustion is 255 kJ /mol smaller in absolute value than that calculated from the structural formula. [Pg.206]

DECAHYDRO- NAPHTHALENE Bicydo [4,4,0] Decane, Naphthalane, Perhydro-naphthalene, Decalin Combustible Liquid, II 2 2 0... [Pg.99]

TETRAHYDRO- NAPHTHALENE 1,2,3,4-Tetra-hydronaphthalene, Tetralln, Tetranap Combustible Liquid 2 0... [Pg.109]


See other pages where Naphthalene, combustion is mentioned: [Pg.486]    [Pg.486]    [Pg.1560]    [Pg.171]    [Pg.337]    [Pg.11]    [Pg.110]    [Pg.742]    [Pg.49]    [Pg.40]    [Pg.176]    [Pg.218]    [Pg.2]    [Pg.359]    [Pg.1176]    [Pg.1635]    [Pg.434]    [Pg.344]    [Pg.554]    [Pg.106]    [Pg.21]    [Pg.52]    [Pg.227]    [Pg.344]    [Pg.178]    [Pg.210]   
See also in sourсe #XX -- [ Pg.360 ]




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Combustion of naphthalene

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