Nitric acid mixtures with water

Investigations on the influence of metals on TNT are of special importance. Extensive studies on the effect of lead, aluminium and iron on TNT in the presence of nitric acid were carried out by Kovache and Thibon [94] as early as in 1918. These investigators found, that when heating TNT with chips of lead, aluminium or iron in the presence of nitric acid diluted with water to a concentration of about 13% of HN03, a product was formed which contained a considerable proportion of the metal, and which was insoluble in toluene, inflammable and sensitive to friction and impact. The products of the reactions of TNT with lead and iron were particularly sensitive. They also could be ignited when heated with nitric acid or with mixtures of nitric and sulphuric acids. 

Mercury nitrate (0 05m). Dissolve 28 1 g mercury nitrate dihydrate, Hg2(N03)2.2H20, in a cold mixture of 500 ml water and 10 ml concentrated nitric acid. Dilute with water to 1 litre. Add 1 drop of pure mercury metal to prevent oxidation. 

Not only can the mother substances, the aromatic hydrocarbons, but all their derivatives, as phenols, amines, aldehydes, acids, etc., undergo similar reactions. But the nitration does not take place in every case with the same ease. In each case, therefore, the most favourable conditions for the experiment must be determined. If a compound is very easily nitrated, the nitration may be effected, according to the conditions, by nitric acid diluted with water, or the substance may be dissolved in a solvent which is not attacked by nitric acid glacial acetic acid is frequently used for this purpose, and then treated with nitric add. The reverse process may also be employed, i.e. the substance is added to a mixture of nitric acid and water, or nitric acid and glacial acetic acid. If a substance is moderately difficult to nitrate, it is added... 

AMILMERCAPTANO (Spanish) (110-66-7) Forms explosive mixture with air (flash point 65°F/18°C). Ignites on contact with concentrated nitric acid. Contact with water, steam, or acids produces toxic and flammable vapors. Incompatible with oxidizers, reducing agents, alkali metals, calcium hypochlorite. 

When treating a mixture of lanthanum oxide and cerium oxide with 50-2(X) parts of nitric acid diluted with water, lanthanum oxide was dissolved, but the residual cerium oxide was not yellow, but brownish-red, and the lanthanum oxide also had a more or less similar reddish tint. From this phenomenon Mosander concluded that a third substance must be present, following in one experiment lanthanum oxide... 

Nitration Phenols are nitrated on treatment with a dilute solution of nitric acid in either water or acetic acid It IS not necessary to use mixtures of nitric and sulfuric acids because of the high reactivity of phe nols... 

The y -phenylenediamiaes are easily obtained by dinitrating, followed by catalyticaHy hydrogenating, an aromatic hydrocarbon. Thus, the toluenediamiaes are manufactured by nitrating toluene with a mixture of sulfuric acid, nitric acid, and 23% water at 330°C which first produces a mixture (60 40) of the ortho and para mononitrotoluenes. Further nitration produces the 80 20 mixture of 2,4- and 2,6-dinitrotoluene. Catalytic hydrogenation produces the commercial mixture of diamiaes which, when converted to diisocyanates, are widely used ia the production of polyurethanes (see Amines, aromatic, DIAMINOTOLUENES) (22). 

Addition of ether to a nitration mixture (2-bromotoluene and cone, nitric acid) diluted with an equal volume of water in a separating funnel led to a low order explosion. This was attributed to oxidation of the ether (possibly containing alcohol) by the... 

The order and timing of the addition of reagents in the KA-process is varied but in a typical procedure three reagents, namely, acetic anhydride, a solution of ammonium nitrate in nitric acid, and solid hexamine dinitrate, are added slowly, in small portions and in parallel, into the reaction vessel which is preheated to 60-80 °C. On completion the reaction mixture is often cooled to 50-60 °C and the RDX filtered and sometimes washed with acetic acid. This process produces a product which melts over a 2 °C range but the RDX still contains up to 10 % HMX as a by-product. Dilution of the reaction mixture with water before removing the RDX produces a very impure product containing numerous unstable linear nitramine-nitrates. Based on the assumption that one mole of hexamine dinitrate produces two mole of RDX the KA-process commonly yields 75-80 % of RDX. 

Preparation of Antimony(V) Oxide. Treat 0.25 g of powdered metallic antimony with 2-3 ml of concentrated nitric acid in a porcelain howl while heating it in a water hath. Consider oxidation to he completed if a sample of the obtained white powder dissolved in an alkali will not reduce an ammonia solution of silver. When oxidation is completed, dilute the reaction mixture with water and separate the precipitate by decantation. Dry the precipitate in a water bath until it is dry, and then in a sand bath (275 °C). What is observed when it is treated with concentrated hydrochloric acid and a sodium hydroxide solution Write the equations of the reactions. How can antimony(lll) oxide be prepared ... 

To 20 gms. (1 mol.) of cold boiled-out 67% nitric acid, 2 gms. of urea in 15 gms. (excess) of absolute alcohol are added, and half of the mixture distilled off on a water bath in a tubulated retort attached to condenser and receiver. 40 gms. of similar nitric acid mixed with 30 gms. of absolute alcohol, and containing 0-5 gm. of urea, are now allowed to drop in through the tubulus from a tap funnel at the same rate as the liquid distils. Water is added to the distillate, the ester which separates is washed several times with cold water, dried over calcium chloride, and distilled from a water bath, the fraction 84°—88° being retained. Care must be taken in this experiment, as the ester is liable to explode when quickly heated. All operations should be carried out behind a metal screen. 

W. C. Holmes measured the f.p. of mixtures of sulphuric acid with up to 50 per cent, of nitric acid. If no water be present so that the total acidity is 100 per cent, there is a minimum at —18-2° when 5-4 per cent. HN03 is present and a maximum at 2-3° with 10-8 per cent. HN03. This corresponds with nitratopentasulphuric... 

Before platinization, electrodes should be cleaned by brief immersion in a solution prepared by combining 3 volumes of 12 M hydrochloric acid with 1 volume of 16 M nitric acid and 4 volumes of water (50% aqua regia). This mixture also can be employed to strip the platinum black from used electrodes. The electrodes are then washed in 16 M nitric acid, rinsed in water, cathodized... 

Since according to Hantzsch the H2N03+ ion is the principal nitrating agent, these reactions could account for the fact that oiganic compounds are best nitrated with a nitric mid sulphuric acid mixture with a water content of 10%. 

On reacting TNT with metals in the presence of mixtures of nitric and sulphuric acids diluted with water similar products were obtained, although the presence of sulphuric acid inhibited their formation to some extent. These products can be formed in production while TNT is being washed free of acid by water, for when most of the sulphuric acid has been removed, the remaining nitric acid is strongly absorbed by molten TNT. 

Summary 70% Nitric acid can be obtained by treating potassium or sodium nitrate with sulfuric acid, mixing with water, and then extracting the acid mixture with methylene chloride. The result is a methylene chloride solution containing 99% nitric acid. This methylene chloride/99% nitric acid solution is then mixed with a calculated amount of water, and then carefully distilled to remove the methylene chloride and leave behind 70% nitric acid. 

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