Preparation of Anhydrous Nitric Acid

Preparation of Anhydrous Nitric Acid. Put 50 g of sodium nitrate into retort 1 made from refractory glass (see Fig. 80) and pour in 100 ml of a 98% solution of sulphuric acid. Carefully heat the retort with the flame of a burner and distil oS a 90-95% nitric acid solution into receiver 4 cooled by a mixture of water and ice. Garry out distillation until the nitrogen oxides in the retort disappear. 

Transfer the prepared fuming nitric acid into the flask of an apparatus for distillation in vacuum (Fig. 91). Coat all the ground-glass joints in the apparatus with moistened phosphoric anhydride or concentrated sulphuric acid. (When pouring over the nitric acid, be ca- 

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Several methods have been suggested for the preparation of anhydrous nitric acid. 

Jousselin [26] prepared nitroguanidine by the action of anhydrous nitric acid or sulphuric acid on guanidine nitrate. The preparation of this substance by the action of sulphuric acid has been developed as an industrial method for the production of nitroguanidine. The method described by Marqueyrol and Loriette [27] follows somewhat different principles. It consists in acting with anhydrous nitric acid on guanidine sulphate which, in turn, is obtained on treating dicyandiamide with sulphuric acid. 

Nitrogen pentoxide can be made by dehydration of anhydrous nitric acid with phosphorus pentoxide and sublimation from the mixture at about 40°. Resublimation with ozone and more phosphorus pentoxide gives pure white crystals which rattle around in the reaction chamber after slight evacuation. Direct oxidation with ozone of nitrogen dioxide prepared by heating lead nitrate is a somewhat better way of making the material. 

Gnehm [22] prepared hexanitrodiphenylamine by the nitration of diphenyl-amine with nitric acid, while Mertens [23] used a mixture of anhydrous nitric acid with concentrated sulphuric acid for the purpose. This method was applied in 1910 for the commercial preparation of hexyl. Since the yields obtained were too low (some 60% of the theoretical), during World War I a method patented in 1895 by the Griesheim Works was introduced, the starting materials being chlorodi-nitrobenzene and aniline. The method consists in the preparation of dinitrodi-phenylamine (m. p. 156-167°C) which is then nitrated in two stages, to obtain first tetranitrodiphenylamine (m. p. 199°C) and then hexyl ... 

Attempts to prepare protactinium pentanitrate by reacting penta-halides with liquid dinotrogen pentoxide have resulted in the formation of HPalNOglfl, possibly as a result of traces of anhydrous nitric acid present in the N Os 49). The presence of the jiroton has not been confirmed by electron spin resonance studies, but infrared results have shown that all the nitrate is covalently bound and vibrations associated with the nitronium and nitrosonium cations were not observed. Niobium and tantalum pentahalides react under similar conditions to form the anhydrous oxytrinitrates, M 0(N0g)3 20, 87). 

Esterification with mixed acids is often suitable for the preparation of carbohydrate nitrates, but sometimes a less vigorous method is required. For this purpose, a solution of anhydrous nitric acid in chloroform was introduced by Koenigs and Knorr and found suitable for preparing... 

Tetranitromethane can be prepared flirough the following four steps 31.5 g of anhydrous nitric acid (d > 1.53) was added into the reaction flask the temperature is controlled below 5 °C with ice bath 51 g of acetic anhydride was slowly added under a nitrogen atmosphere dropwise after the adding, the system is cooled down to room temperature naturally. The mixture is added to a flask containing 300 ml of water and steaming distilled, and tetranitromethane are distilled out with the first 20 ml distilled-out solution the upper layer of water is removed, washed first with... 

Preparative Method anhydrous nitric acid can be prepared by distilling fuming nitric acid from an equal volume of concentrated sulfuric acid. 

Nitronium tetrafluoroborate was first prepared by adding a mixture of anhydrous hydrofluoric acid and boron trifluoride to a solution of dinitrogen pentoxide in nitromethane. Nitric acid can be used in place of dinitrogen pentoxide, and by replacing boron trifluoride by other Lewis-acid fluorides Olah and his co-workers prepared an extensive series of stable nitronium salts. ... 

A convenient method for the preparation of nitronium tetrafluoroborate involves treating a mixture of absolute nitric acid or an alkyl nitrate " with anhydrous hydrogen fluoride and an excess of boron trifluoride. Pure nitronium triflate can be synthesized by treating triflic anhydride or triflic acid with dinitrogen pentoxide in an inert solvent. Other methods for nitronium salt synthesis are discussed by Olah. ... 

Nickel nitrate hexahydrate may be prepared by several methods based on the reaction of dilute nitric acid on nickel powder, nickel oxide or nickel carbonate. The reaction is exothermic and requires controlled cooling during production. The hexahydrate can be dehydrated to anhydrous salt by treatment with fuming nitric acid. 

Another method of nitroguanidine preparation is that of Marqueyrol and Loriette mentioned already [27]. According to Aubertein [61], here nitroguanidine is formed by the following reactions dicyandiamide is heated with 60% sulphuric acid at 150°C to form guanidine sulphate which however is not isolated. Instead, the reaction mixture is treated directly with a 30% excess of anhydrous nitric add at 25°C. Nitroguanidine, m.p. 257°C, is prepared in this manner in a 91 % yield. 

It seems probable that this compound may find a practical application. It was first prepared by Bennett [75] by the nitration of diphenylethylenediamine with a mixture of concentrated sulphuric acid and anhydrous nitric acid at 30-35°C. Later Cox [76] worked out a practical method for its use in detonators. 

Anhydrous Nitric Acid. One hundred per cent nitric acid may be prepared by distillation of a mixture of concen-... 

Trichloro-2,4,6-trinitrobenzene (m. p. 187°C) can be prepared by the nitration of 1,3,5-trichlorobenzene with anhydrous nitric acid and oleum (Jackson and Wing [42]). However, according to van Ryn [43] the yield is poor. 

The compound may be prepared in 70% yield by the nitration of phenothiazine with a mixture of 98% nitric acid and anhydrous sulphuric acid at 60°C. In addition to nitration, oxidation of the sulphur atom also takes place, resulting in the formation of the sulphoxide. 

Summary Tetraaniline can be prepared by nitrating meta-nitroniline with anhydrous nitric acid in the presence of concentrated sulfuric acid. The resulting reaction mixture is then stirred, and the desired product allowed to precipitate. The precipitated product is then filtered-off, washed with acid, and then with water. The moist product is then vacuum dried or air-dried. Commercial Industrial note For related, or similar information, see Application No. 701,582, May 14, 1991, by Rockwell International Corporation, to James F. Weber, Moorpark, CA. Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned explosive, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned explosive for laboratory, educational, or research purposes. 

Chromium(VI) oxide nitrate and vanadium(V) oxide nitrate were first prepared by Schmeisser and Lutzow by the reaction of chromium(VI) oxide and vanadium(V) oxide with nitrogen(V) oxide. The nitrogen(V) oxide was prepared in the solid state by dehydration of fuming nitric acid with phosphorus(V) oxide. The method described below simplifies the preparation of anhydrous nitrogen(V) oxide and shortens significantly the time required. The products obtained can be protected from hydrolysis by totally excluding water from the all-glass system. 

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