Nitrobenzene Uses

Aniline accounted for almost 97% of the United States demand for nitrobenzene in 2001. The other three percent is used in p-aminophenol, dyes and pigments and as a chemical intermediate and solvent. 

Caprolactam is a white, hygroscopic, crystalline solid with a characteristic odor. Its basic properties are summarized in Table 21.1. Most caprolactam is used to make nylon 6, which is the starting material for fibers that have many uses in textile manufacture and in the industrial sector. 

Chemical Formula Molecular Weight Melting Point (°C) 

Polymerization is caprolactam s most important chemical property. The ring is hydrolyzed at 260 to 270°C. Liner polymer chains are formed by polycondensation. Caprolactam also reacts directly by polyaddition with the polymer chains. These reactions lead to an equilibrium between the polymer and caprolactam that favors a 90% conversion to polymer264. 

All commercial caprolactam processes are based on benzene or toluene. These processes employ cyclohexanone, cyclohexane or toluene as starting materials. Large-scale industrial processes are multistage processes in which ammonium sulfate and sometimes organic compounds are formed as byproducts. At least seven processes are used commercially254,266. And each of these processes still has room for improvement. 

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Occurs in the high-boiling fraction of coal tar. Most conveniently prepared by Skraup s reaction by healing a mixture of aniline, glycerol, sulphuric acid and nitrobenzene. Used in the manufacture of dyestuffs, and pharmaceutical products. 

The photoreduction of nitrobenzene using p5o ex filtered light from a medium pressure mercury arc was studied in petroleum, toluene, ether, 2-propanol, tert-butyl alcohol, diethylamine, triethylamine, aqueous solutions of 2-propanol and diethylamine and also in aqueous t-butylalcohol containing sodium boro-hydiide 3 >. Varying amounts of aniline, azo- and azoxybenzene were obtained. In the presence of a fourty-fold excess of benzophenone, a six-fold increase in the rate of aniline formation in ethereal solution was observed, and aniline formation was completely suppressed by addition of biacetyl or octafluomaphthalene Since unreacted nitrobenzene could be recovered in these experiments, it is demonstrated that the triplet state of nitrobenzene was quenched. 

Ito [85] investigated the sonoelectropolymerisation of thiophene (0.3 mol dm ) in nitrobenzene using tertiary butyl perchlorate as the electrolyte, platinum electrodes... 

V. Jagannadham and S. Steenken, J. Amer. Chem. Soc. 106, 6542 (1984). The reaction of RCHOH, generated by pulse radiolysis, was studied with p-substituted nitrobenzenes using time-resolved optical and conductance detection. The radical anion of the nitrobenzene is produced directly and indirectly. 

Vanura, R, Makrlik, E. Extraction of microamounts of yttrium from water into nitrobenzene using hydrogen dicarbollylcobaltate in the presence of 15-crown-5. J. Radioanal. Nucl. Chem. (2006), 267 (1), 251-254. 

The aniline formed simultaneously can be removed by adding lime, and steam-distilling the mixture. After filtering calcium sulphate from the residue, crystals of aminophenol can be obtained by evaporation. The average yield is reported to be 50 per cent, of the nitrobenzene used. 

An even wider variation of preparation procedures for the palladium catalyst was investigated for the hydrogenation of nitrobenzene using a falling-film microreactor [321,323],... 

Hydroxylation is also induced in good yields by the photolysis of alkanes in nitrobenzene. Using a high pressure mercury lamp, the tertiary > secondary > primary selectivities observed have been 300 19 1 (pyrex filter) and 110 7 1 (vycor filter). No retention of co guration was observed in these reactions consequently, a free radical mechanism was invoked. ... 

Several interesting fluoroaromatic derivatives, e.g. 3, can be obtained in good to excellent yield by fluorodenitration with potassium fluoride in sulfolane using phthaloyl fluoride (2) or tetrafluorophthaloyl fluoride as nitrite ion traps.131,2-Difluorobenzenes 4 are formed from 1 -fluoro-2-nitrobenzenes and l-chloro-2-nitrobenzenes using this method. 

N-ACETYL-N-PHENYLHYDROXrUMINE VIA CATALYTIC TRANSFER HYDROGENATION OF NITROBENZENE USING HYDRAZINE AND RHODIUM OH CARBON (Acetaaide. N-hydroxy-N-pheny1-)... 

Fig. 15 Temperature dependence of the gel-fraction yield during the preparation of poly(styrene) gels (circles) and cryogels (squares) in nitrobenzene using 4,4 -xylylene dichloride as a crosslinker. The temperature scale is the relative temperature AT (as explained in Sect. 1). Polymer and crosslinker concentrations in the initial nitrobenzene solution were 0.3 M and 9.1 mol%, respectively (both with respect to the styrene units). (Plotted based on the data from [27])...

Bhatkhande DS, Pangarkar VG, Beenackers AACM. (2003) Photocatalytic degradation of nitrobenzene using titanium dioxide and concentrated solar radiation chemical effects and scale up. Water Res., 37 1223-1230. 

Bhatkhande DS, Kamble SP, Sawant SB, Pangarkar VG. (2004) Photocatalytic and photochemical degradation of nitrobenzene using artificial UV radiation. Chem. Eng. J., 102(3) 283-290. 

Nitrobenzene Used in the manufacture of aniline dyes and explosives also in the manufacture of perfumes, liqueurs and confectionery Greenish-blue discoloration of the mucous membranes, bluish-black line on the gums ... 

Four steps of synthesis for BP503A were used. First, 4-methoxy-4 -pentanoylbiphenyl (1) was synthesized by the Friedel-Crafts reaction between 4-methoxybiphenyl and pentanoylchloride in nitrobenzene using aluminum chloride as a catalyst. We reduced the carbonyl moiety of 1 to the methylene group with... 

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