Sodium nitrate decomposition

Potassium Nitrate. Potassium nitrate, known but Httle used as a fertilizer for many years, may be reclaimed as a by-product of the production of sodium nitrate from natural deposits of caflche in Chile. KNO also has been produced by the double decomposition reaction between sodium nitrate and potassium chloride ... 

Manufacture. Historically, ammonium nitrate was manufactured by a double decomposition method using sodium nitrate and either ammonium sulfate or ammonium chloride. Modem commercial processes, however, rely almost exclusively on the neutralization of nitric acid (qv), produced from ammonia through catalyzed oxidation, with ammonia. Manufacturers commonly use onsite ammonia although some ammonium nitrate is made from purchased ammonia. SoHd product used as fertilizer has been the predominant form produced. However, sale of ammonium nitrate as a component in urea—ammonium nitrate Hquid fertilizer has grown to where about half the ammonium nitrate produced is actually marketed as a solution. 

Barium nitrate is prepared by reaction of BaCO and nitric acid, filtration and evaporative crystallization, or by dissolving sodium nitrate in a saturated solution of barium chloride, with subsequent precipitation of barium nitrate. The precipitate is centrifuged, washed, and dried. Barium nitrate is used in pyrotechnic green flares, tracer buUets, primers, and in detonators. These make use of its property of easy decomposition as well as its characteristic green flame. A small amount is used as a source of barium oxide in enamels. 

Den Hertog and Overhoff - observed that when pyridine in sulfuric acid is added to molten potassium sodium nitrate the 3-nitro derivative is formed at 300°C, whereas at 450°C 2-nitropyridme is the main product. The latter is probably a free-radical process. Schorigin and Toptschiew obtained 7-nitroquinoline by the action of nitrogen peroxide on quinoline at 100°C, possibly through the homolytic addition of NOa. Laville and Waters reported that during the decomposition of pernitrous acid in aqueous acetic acid, quinoline is nitrated in the 6- and 7-positions. They considered that the reaction proceeds as shown in Scheme 3. 

In the other method, particularly popular in Germany, the ammonium nitrate is replaced by an equimolar mixture of ammonium chloride and potassium or sodium nitrate. The reaction between the salts, which gives potassium or sodium chloride and ammonium nitrate or its decomposition products, is relatively slow and does not occur to a marked extent when the explosive is fired in an unconfined condition. This method of working is particularly effective in reducing the power of an explosive in the unconfined condition. Used alone it has not proved popular in Britain, because of the low power which tends to be developed under practical firing conditions. Moreover, the finely divided sodium chloride smoke which is produced by the explosive tends to be unpleasant for the miners. 

Magnesium nitrate has been reported to undergo spontaneous decomposition in DMF, (possibly as a result of hydrolysis of the hexahydrate above its m.p., 90°C to liberate nitric acid). Although this effect has not been observed with other nitrates, reaction mixtures with hydroly sable nitrates should be treated with care. See Sodium nitrate Jute, Magnesium chloride... 

A study of the kinetics in attack of magnesium by molten sodium nitrate indicates that decomposition of the nitrate releases oxygen atoms which oxidise the metal so exothermally that ignition ensues. 

A novel, mild system for the direct nitration of calixarenes has been developed using potassium nitrate and aluminum chloride at low temperature. The side products of decomposition formed under conventional conditions are not observed in this system, and the p-nitro-calixarenes are isolated in 75-89% yields.17 Such Friedel-Crafts-type nitration using nitryl chloride and aluminum chloride affords a convenient system for aromatic nitration.18 Nitryl chloride was previously prepared either by the oxidation of nitrosyl chloride or by the reaction of chlorosulfonic acid with nitric acid. However, these procedures are inconvenient and dangerous. Recently, a mixture of sodium nitrate and trimethysilyl chloride (TMSC1) has been developed as a convenient method for the in situ generation of nitryl chloride (Eq. 2.6). 

Ammonium nitrate alternatively may be prepared by double decomposition reactions of ammonium salt with a nitrate salt e.g., ammonium sulfate and sodium nitrate ... 

The nitrate is also obtained from the chloride by acting upon it with sodium nitrate, when double decomposition takes place and a light carmine-red precipitate is formed. This is recrystallised from water on the further addition of sodium nitrate. The salt is anhydrous. 

The world s consumption of sodium nitrate in 1912 was 2,460,000 tons and in 1914, 2,633,000 tons. Sodium nitrate can be converted into potassium nitrate by double decomposition with potassium chloride,7 with potassium hydroxide 8 or with potassium carbonate and also by first converting it into barium nitrate and... 

Lead azide is insoluble in an aqueous solution of ammonia. Acetic acid causes its decomposition but it is soluble in water and concentrated solutions of sodium nitrate, sodium acetate or ammonium acetate. There are fairly big differences of solubility, depending on temperature. 

It is a practice in some countries to add a small amount of sodium hydrogen carbonate to the powder dough, to neutralize dinitrogen tetroxide evolved during the decomposition of the powder. This would lead to formation of sodium nitrate... 

By the double decomposition of ammonium sulfate and sodium nitrate in solution (NH4),St>4 + 2NaNO, - 2NH4NO, + Na,S04. This process, patented by Freeth and Cocksedge (Ref 13), was an economical one up to the time of the development of synthetic NH, and of HNO, by ammonia oxidation... 

The nitration process was performed in the usual equipment, controlling the temperature, which should not exceed 25°C, by cooling with a 35% sodium nitrate solution, the temperature of which was — 15°C. Under these conditions nitration lasted about 25 min. When the nitration was completed, the contents of the nitrator were cooled down to 15°C and transferred to a separator. The separation was accomplished within 7 min and the spent acid was immediately sent to the denitration unit. Special care had to be taken to ensure that no spent add remained in the tank, because decomposition of the residual dinitrodiethylene glycol may start within a few hours. None the less such decomposition is less hazardous than that of nitroglycerine, since dinitrodiethylene glycol produces a spontaneous explosion only in the instance when the tank is confined. 

Nitric acid is manufactured at the present day by one of three processes (i) By the direct oxidation of nitrogen in the electric arc as indicated in connection with the fixation of nitrogen (ii) By oxidation of ammonia as indicated in connection with that compound and (iii) By the decomposition of sodium nitrate with sulphuric acid. Some chemical changes involved in the third reaction have just been discussed. The plant employed consists of (i) the distilling apparatus (ii) the condensing system (iii) the receiving vessel (iv) the bleaching system and (v) the absorption apparatus. 

Tetraphenylborate (TPB) was used at Savannah River to recover cesium from alkaline solutions, but attempts to treat HLW tanks with TPB resulted in the production of benzene (a TPB decomposition product) at levels that did not permit the safe operation of the process.8 Crown ethers and dicarbollides were proposed as extractants to remove cesium from acidic HAW, but these compounds are not selective enough to allow cesium to be removed from solutions containing large amounts of nitric acid or sodium nitrate.9 Dicarbollides were used in Russia at industrial scale to recover cesium from HAW, but the removal of cesium was only possible after partial denitration of the liquid waste.10... 

Other processes for making chlorine include sodium manufacture, caustic potash manufacture, hydrogen chloride decomposition, the nitro-syl chloride (NOC1) process, and a process where salt is treated with nitric acid to form sodium nitrate and chlorine with nitrosyl chloride (containing 4 to 10% nitrogen tetroxide) as a by-product. The nitrosyl chloride vapor is placed in contact with oxygen to produce nitrogen tetroxide and chlorine ... 

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