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Benzene and Toluene

The reactor effluent is thus likely to contain hydrogen, methane, benzene, toluene, and diphenyl. Because of the large differences in volatility of these components, it seems likely that partial condensation will allow the effluent to be split into a vapor stream containing predominantly hydrogen and methane and a liquid stream containing predominantly benzene, toluene, and diphenyl. [Pg.110]

The temperature of the phase split is well above the critical temperatures of both hydrogen and methane, leading to large K values. On the other hand, the K values of the benzene, toluene, and diphenyl are very low, and hence the assumption of a sharp split in Example 4.2 was a good one. [Pg.115]

BTX A mixture of low boiling point aromatics, i.e. benzene, toluene and xylenes. [Pg.69]

Benzene, toluene and xylenes are used either as solvents or as basic intermediates for the chemical and petrochemical industries. [Pg.273]

The critical factor for any method involving an approximation or an extrapolation is its range of application. Liu et al. [15] demonstrated that the approach performed well for mutations involving the creation or deletion of single atoms. The method has also been successfully applied to the prediction of the relative binding affinities of benzene, toluene and o-, p-, and m-xylene to a mutant of T4-lysozyme [16]. In both cases, however, the perturbation to the system was small. To investigate range over which the extrapolation may... [Pg.159]

The rates of nitration of benzene, toluene, and ethylbenzene in solutions of nitric acid c. 3-7 mol 1 ) in nitromethane were independent... [Pg.32]

The kinetics of the nitration of benzene, toluene and mesitylene in mixtures prepared from nitric acid and acetic anhydride have been studied by Hartshorn and Thompson. Under zeroth order conditions, the dependence of the rate of nitration of mesitylene on the stoichiometric concentrations of nitric acid, acetic acid and lithium nitrate were found to be as described in section 5.3.5. When the conditions were such that the rate depended upon the first power of the concentration of the aromatic substrate, the first order rate constant was found to vary with the stoichiometric concentration of nitric acid as shown on the graph below. An approximately third order dependence on this quantity was found with mesitylene and toluene, but with benzene, increasing the stoichiometric concentration of nitric acid caused a change to an approximately second order dependence. Relative reactivities, however, were found to be insensitive... [Pg.224]

The classification of hydrocarbons as aliphatic or aromatic took place m the 1860s when It was already apparent that there was something special about benzene toluene and their derivatives Their molecular formulas (benzene is CgHg toluene is C7Hj ) indicate that like alkenes and alkynes they are unsaturated and should undergo addition reac tions Under conditions m which bromine for example reacts rapidly with alkenes and alkynes however benzene proved to be inert Benzene does react with Bi2 m the pres ence of iron(III) bromide as a catalyst but even then addition isn t observed Substitu tion occurs instead ... [Pg.424]

To illustrate substituent effects on rate consider the nitration of benzene toluene and (trifluoromethyl)benzene... [Pg.488]

The principle of headspace sampling is introduced in this experiment using a mixture of methanol, chloroform, 1,2-dichloroethane, 1,1,1-trichloroethane, benzene, toluene, and p-xylene. Directions are given for evaluating the distribution coefficient for the partitioning of a volatile species between the liquid and vapor phase and for its quantitative analysis in the liquid phase. Both packed (OV-101) and capillary (5% phenyl silicone) columns were used. The GG is equipped with a flame ionization detector. [Pg.611]

Benzene, toluene, and a mixed xylene stream are subsequently recovered by extractive distillation using a solvent. Recovery ofA-xylene from a mixed xylene stream requires a further process step of either crystallization and filtration or adsorption on molecular sieves. o-Xylene can be recovered from the raffinate by fractionation. In A" xylene production it is common to isomerize the / -xylene in order to maximize the production of A xylene and o-xylene. Additional benzene is commonly produced by the hydrodealkylation of toluene to benzene to balance supply and demand. Less common is the hydrodealkylation of xylenes to produce benzene and the disproportionation of toluene to produce xylenes and benzene. [Pg.175]

Nitrations can be performed in homogeneous media, using tetramethylene sulfone or nitromethane (nitroethane) as solvent. A large variety of aromatic compounds have been nitrated with nitronium salts in excellent yields in nonaqueous media. Sensitive compounds, otherwise easily hydroly2ed or oxidized by nitric acid, can be nitrated without secondary effects. Nitration of aromatic compounds is considered an irreversible reaction. However, the reversibihty of the reaction has been demonstrated in some cases, eg, 9-nitroanthracene, as well as pentamethylnitrobenzene transnitrate benzene, toluene, and mesitylene in the presence of superacids (158) (see Nitration). [Pg.561]

Benzene, toluene, and other aromatics that are easily nitrated can sometimes be nitrated using acids having zero NO/ concentrations (see Fig. 1). Two explanations for this are (/) NO/ is actually present but in concentrations too low to be measured by Raman spectra, and (2) NO/ is hydrated to form H2N0" 2> which is also a nitrating agent. [Pg.33]

Benzene, toluene, and xylene are made mosdy from catalytic reforming of naphthas with units similar to those already discussed. As a gross mixture, these aromatics are the backbone of gasoline blending for high octane numbers. However, there are many chemicals derived from these same aromatics thus many aromatic petrochemicals have their beginning by selective extraction from naphtha or gas—oil reformate. Benzene and cyclohexane are responsible for products such as nylon and polyester fibers, polystyrene, epoxy resins (qv), phenolic resins (qv), and polyurethanes (see Fibers Styrene plastics Urethane POLYiffiRs). [Pg.216]

Aromatic Hydrocarbons. Sulfolane is used principally as a solvent for extraction of benzene, toluene, and xylene from mixtures containing aHphatic hydrocarbons (33—37). The sulfolane process was introduced in 1959 by SheU Development Company, and that process is Hcensed by Universal OH Products. A sulfolane extraction process is also Hcensed by the Atlantic Richfield Company. In 1994, worldwide consumption was estimated at ca 6974 t/yr of sulfolane for 137 sulfolane extraction units (see Bix processes Extraction, liquid-liquid Xylenes and ethylbenzene). [Pg.69]

Toluene, Benzene, and BTX Reeoveiy. The composition of aromatics centers on the C - and Cg-fraction, depending somewhat on the boihng range of the feedstock used. Most catalytic reformate is used directiy in gasoline. That part which is converted to benzene, toluene, and xylenes for commercial sale is separated from the unreacted paraffins and cycloparaffins or naphthenes by hquid—hquid extraction or by extractive distillation. It is impossible to separate commercial purity aromatic products from reformates by distillation only because of the presence of azeotropes, although comphcated further by the closeness in boihng points of the aromatics, t/o-paraffin, and unreacted C -, C -, and Cg-paraffins. [Pg.179]

Common examples of compounds that are amenable to carbon adsorption are aromatics (benzene, toluene) and chlorinated organics (trichloroethylene, trichloroethane [71-55-6, 75 -(9(9-j5y, tetrachloroethylene, polychlorinated biphenyls (PCBs), DDT /T(9-77-77, pentachlorophenol [87-86-5J. Compounds that are not adsorbed effectively by carbon include ethanol [64-17-5], diethylene glycol [111-46-6], and numerous amines (butylamine [109-73-9, 13952-84-6, 75-64-9], triethanolamine [102-71-6], cyclohexylamine [108-91-8], hexamethylenediamine [108-91-8] (1). Wastewater concentrations that are suitable for carbon adsorption are generally less than 5000 mg/L. [Pg.160]

Transall lation. Two molecules of toluene are converted iato one molecule of benzene and one molecule of mixed xylene isomers ia a sequence called transalkylation or disproportionation. Economic feasibiUty of the process strongly depends on the relative prices of benzene, toluene, and xylene. Operation of a transalkylation unit is practical only when there is an excess of toluene and a strong demand for benzene. In recent years, xylene and benzene prices have generally been higher than toluene prices so transalkylation is presendy an attractive alternative to hydrodealkylation (see also Btx... [Pg.42]

Bismuth ttiiodide may be prepared by beating stoichiometric quantities of the elements in a sealed tube. It undergoes considerable decomposition at 500°C and is almost completely decomposed at 700°C. However, it may be sublimed without decomposition at 3.3 kPa (25 mm Hg). Bismuth ttiiodide is essentially insoluble in cold water and is decomposed by hot water. It is soluble in Hquid ammonia forming a red triammine complex, absolute alcohol (3.5 g/100 g), benzene, toluene, and xylene. It dissolves in hydroiodic acid solutions from which hydrogen tetraiodobismuthate(Ill) [66214-37-7] HBil 4H2O, may be crystallized, and it dissolves in potassium iodide solutions to yield the red compound, potassium tetraiodobismuthate(Ill) [39775-75-2] KBil. Compounds of the type tripotassium bismuth hexaiodide [66214-36-6] K Bil, are also known. [Pg.129]

Processes for hydrogen gasification, hydrogen pyrolysis, or coking of coal usually produce Hquid co-products. The Hygas process produces about 6% Hquids as benzene, toluene, and xylene. Substitution of petroleum residuum for the coal-derived process oil has been used in studies of coal Hquefaction and offers promise as a lower cost technology (104). [Pg.237]

Physical properties of some commercially available polyamines appear in Table 1. Generally, they are slightly to moderately viscous, water-soluble Hquids with mild to strong ammoniacal odors. Although completely soluble in water initially, hydrates may form with time, particularly with the heavy ethyleneamines (TETA, TEPA, PEHA, and higher polyamines), to the point that gels may form or the total solution may soHdify under ambient conditions. The amines are also completely miscible with alcohols, acetone, benzene, toluene and ethyl ether, but only slightly soluble in heptane. [Pg.40]

Some catalysts exposed to air stripping off-gas were subject to deactivation. However, using a catalytic oxidizer at a U.S. Coast Guard faciUty (Traverse City, Mich.) for the destmction of benzene, toluene, and xylene stripped from the groundwater, the catalytic oxidization unit operated at 260 to 315°C, and was able to achieve 90% destmction efficiency (see Groundwatermonitoring). [Pg.514]

More up-to-date data of this process are employed in a study by Rase (Fixed Bed Reactor Design and Diagnostics, Butterworths, 1990, pp. 275-286). In order to keep the pressure drop low, radial flow reactors are used, two units in series with reheating between them. Simultaneous formation of benzene, toluene, and minor products is taken into account. An economic comparison is made of two different catalysts under a variety of operating conditions. Some of the computer printouts are shown there. [Pg.2081]

Plants have now been installed by some manufacturers to produce ethylbenzene via catalytic reforming processes. The reforming process is one which converts aliphatic hydrocarbons into a mixture of aromatic hydrocarbons. This may be subsequently fractionated to give benzene, toluene and a xylene fraction from which ethylbenzene may be obtained. [Pg.428]

Benzene, toluene, and aromatics of similar reactivity can be nitrated using YbCOjSCFjjj and 69% nitric acid in an inert solvent. ... [Pg.573]


See other pages where Benzene and Toluene is mentioned: [Pg.114]    [Pg.5]    [Pg.273]    [Pg.138]    [Pg.232]    [Pg.410]    [Pg.171]    [Pg.172]    [Pg.175]    [Pg.175]    [Pg.165]    [Pg.527]    [Pg.163]    [Pg.343]    [Pg.389]    [Pg.170]    [Pg.41]    [Pg.42]    [Pg.306]    [Pg.313]    [Pg.201]    [Pg.234]    [Pg.236]    [Pg.435]    [Pg.607]   
See also in sourсe #XX -- [ Pg.47 ]




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Benzene, toluene, and xylenes

Benzene, toluene, ethylbenzene, and xylene

Benzene, toluene, ethylbenzene, and xylene BTEX)

Dealkylation of toluene and xylenes to benzene

Determination of Benzene, Toluene and Xylenes (BTX)

Exchange of Toluene and Benzene

Fractional distillation separation of benzene and toluene

Liquid benzene and toluene

Nitration of Benzene and Toluene

Production of benzene, toluene and xylenes

Vapor pressure of benzene and toluene

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