Nitration with mixed acid

To solve some of the environmental problems of mixed-acid nitration, we were able to replaee sulfuric acid with solid superacid catalysts. This allowed us to develop a novel, clean, azeotropic nitration of aromatics with nitric acid over solid perfluorinated sulfonic acid catalysts (Nafion-H). The water formed is continuously azeotroped off by an excess of aromatics, thus preventing dilution of acid. Because the disposal of spent acids of nitration represents a serious environmental problem, the use of solid aeid eatalysts is a significant improvement. [Pg.105]

Red Water — which can be almost black at times - also contains dissolved TNT however, it is not an incidental stream like Pink Water it is a major by-product stream from TNT manuf. The mixed-acid nitration of toluene yields not only 2,4,6-trinitrotoluene, the desired product, but also a host of other isomers and by-products amounting to approx 4.5% of the total yield and it is necessary to remove them from the product. They are removed by extraction with a Na sulfite—Na carbonate soln which sulfonates and dissolves them the extract is called Red Water. Red Water is a very complex and somewhat variable mixt containing 15% or so of sulfonated or sellited nitrobodies and a number of inorganic salts. Typical components are w, NajSOj—NaS04, NaN02— NaNOj, sulfonated or... [Pg.797]

Nitration to 2,3,4,6-tetranitroaniline proved unsafe in mixed acid at 30-50°C. Efficient and safe nitration at 20-30°C was obtained by dissolving the substrate in sulfuric acid, then adding mixed acid (made with oleum) thereto. [Pg.763]

A number of secondary high explosives containing both nitramine and nitrate ester functionality have been reported. Aliphatic examples include A-nitrodiethanolamine dinitrate (DINA) (110), prepared from the nitration of diethanolamine with nitric acid-acetic anhydride in the presence of zinc chloride,and A,A -dinitro-A,A -bis(2-hydroxyethyl)oxamide dinitrate (NENO) (111), prepared from the mixed acid nitration of A,lV -bis(2-hydroxyethyl) oxamide . [Pg.114]

The nitration of dinitrotoluene to TNT requires the use of mixed acid fortified with oleum, and the use of elevated temperature, which produces its own pollutants and impurities, including tetranitromethane and nitrogen oxides. An excellent discussion of industrial TNT production has been given by Urbahski. ... [Pg.135]

Trinitrobenzene is present in crude TNT manufactured by mixed acid nitration and results from methyl group oxidation followed by decarboxylation." In fact, a convenient method for the synthesis of 1,3,5-trinitrobenzene involves oxidation of 2,4,6-trinitrotoluene with a solution of sodium dichromate in sulfuric acid, followed by decarboxylation of the resulting 2,4,6-trinitrobenzoic acid in boiling water." 1,3,5-Trinitrobenzene is prepared from 2,4,6-trinitro-m-xylene by a similar route." 2,4,6-Trinitroanisole can be prepared from the... [Pg.143]

A,A -Bis(3-aminopicryl)-l,2-ethanediamine (108) (m.p. 275 °C) is prepared from the reaction of ethylenediamine with two equivalents of 3-chloro-2,4,6-trinitroaniline. " The same chemists reported 3,3 -diamino-2,2 4,4, 6,6 -hexanitrodiphenylamine (109), a heat resistant explosive (m.p. 232-237 °C) prepared from the reaction of l,3-dichloro-4,6-dinitrobenzene with 3-chloroaniline followed by mixed acid nitration and subsequent chloro group displacement with ammonia. The potassium salt of 3,3 -diamino-2,2, 4,4, 6,6 -hexanitrodiphenylamine shows very high thermal stability. " ... [Pg.165]

Desseigne prepd by reacting ethylamine with dinitrochlorobenzene, followed by mixed acid nitration at 40-50°... [Pg.192]

After nitration the batch was poured on cracked ice with stirring and the trinitrate dissolved in aqueous mixed acid extracted with factory ether the ethereal soln was... [Pg.246]

Kobe and Fort man (Ref 11), in summing up their work and the work of other investigators on the mixed acid nitration of the MNT s (o-MNT in particular) through 1961, conclude 1) ... the products of the nitration of o-nitrotoluene are 2,4- and 2,6-dinitrotoluene in the ratio of 2 to 1, respectively, with only trace quantities of the other possible isomers formed. .2). . the... [Pg.802]

Huttel (55CB1577) also reported that the mixed acid nitration of 3-methyl-5-phenylpyrazole gives the 4-nitro-5-(4-nitrophenyl) product and that the nitration of 3,5-diphenylpyrazole with an excess of nitric acid forms 4-nitro-3,5-bis (4-nitrophenyl)pyrazoIe. [Pg.228]

Considering firstly the data for the 64% sulphuric mix the surface DOS as assessed by ESCA utilizing at MgK source is essentially established after 1 sec. exposure and remains constant thereafter. The diffusion of nitrating mix into the bulk leads to a time dependent DOS which tends to approach that of the surface. As the sulphuric content is increased and water content decreased the surface DOS decreases. In terms of competitive equilibria we might anticipate that as the sulphuric content increases the formation of sulphate esters becomes relatively more favored. The suggestion has been made that in mixed acid nitrations the sulphuric acid does not penetrate the bulk (14) and on this basis we might anticipate significant differences in surface and bulk chemistries irrespective of time scale. ESCA has demonstrated this in detail for the first time. Thus for both the 70% mix and the 75% sulphuric mixes the DOS of the surface is actually lower than for the bulk and work recently completed has shown that with a TiK X-ray source the DOS is also close to that for the bulk. [Pg.289]

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