Sodium nitrate manufacturing

Hitec Heat-Transfer Salt. Hitec heat-transfer salt, manufactured by Coastal Chemical Co., is an eutectic mixture of water-soluble inorganic salts potassium nitrate (53%), sodium nitrite (40%), and sodium nitrate (7%). It is suitable for Hquid-phase heat transfer at temperatures of 150—540°C. 

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. 

Sodium nitrate is used as a fertiliser and in a number of industrial processes. In the period from 1880—1910 it accounted for 60% of the world fertiliser nitrogen production. In the 1990s sodium nitrate accounts for 0.1% of the world fertiliser nitrogen production, and is used for some specific crops and soil conditions. This decline has resulted from an enormous growth in fertiliser manufacture and an increased use of less expensive nitrogen fertilisers (qv) produced from synthetic ammonia (qv), such as urea (qv), ammonium nitrate, ammonium phosphates, ammonium sulfate, and ammonia itself (see Ammonium compounds). The commercial production of synthetic ammonia began in 1921, soon after the end of World War I. The main industrial market for sodium nitrate was at first the manufacture of nitric acid (qv) and explosives (see Explosives and propellants). As of the mid-1990s sodium nitrate was used in the production of some explosives and in a number of industrial areas. 

As of 1996 world production of sodium nitrate was about 520,000 metric tons annually. Of this quantity, some 450,000 t (86%) are produced in Chile from natural deposits by SQM Nitratos and distributed worldwide by several affOiates, eg, Chilean Nitrate Corporation in the United States and Nitrate Sales International in Belgium. The remainder, ca 70,000 t, is manufactured mainly in Europe, Japan, and Russia, generally as a by-product of nitric acid production. Additionally, China is known to manufacture some unknown but significant volumes of sodium nitrate for domestic use. 

Technical Grades. Chile s SQM Nitratos is the largest producer of technical-grade NaNO, making ca 170,000 t/yr. About 70,000 t/yr are manufactured in countries such as Germany (BASF), Japan (Mitsubishi), and others. Sodium nitrate has not been manufactured in the United States since Olin Corporation stopped production in 1988. 

Additionally, it is a source of sodium oxide and a fluidizing agent. The amount of sodium nitrate added in the glass manufacture process is up to 2 wt % of the total raw material. 

In the manufacture of explosives, sodium nitrate is used mainly in blasting agents. In slurries and emulsions, sodium nitrate improves stabiUty and sensitivity. It also improves the energy balance because sodium nitrate replaces water, so that more fuel can be added to the formulation. Sodium nitrate reduces crystal size of slurries, which in turn increases detonating speed. In dynamites sodium nitrate is used as an energy modifier. Typical content of sodium nitrate is 20—50 wt % in dynamites, 5—30 wt % in slurries, and 5—15 wt % in emulsions. Sodium nitrate is used also in permissible dynamites, a special type of dynamite for coal (qv) mining. 

Another large appHcation is as an ingredient in the production of charcoal briquettes. The amount of sodium nitrate used in charcoal briquette manufacture depends on the type and amount of wood and coal used. Typically charcoal briquettes contain up to almost 3% sodium nitrate. Sodium nitrate is also used in the manufacture of enamels and porcelain as an oxidizing and fluxing agent. In porcelain—enamel frits used for metal coating, the amount of sodium nitrate in a batch varies with the various metal bases to be coated, typically from about 3.8 to 7.8 wt %. 

It is available commercially from several routes including as a product from the manufacture of sodium nitrate from sodium chloride and nitric acid, and from a process involving the passage of ammonia and air over heated platinum and treating the nitric oxide so formed with oxygen. 

Similar to other types of water treatment, AC filtration is effective for some contaminants and not effective for others. AC filtration does not remove microbes, sodium, nitrates, fluoride, and hardness. Lead and other heavy metals are removed only by a very specific type of AC filter. Unless the manufacturer states that its product will remove heavy metals, one should assume that the AC filter is not effective in removing them. 

Sulfuric acid is used in the manufacture of nitric acid, too. Combining sulfuric acid with sodium nitrate produces sodium sulfate and nitric acid ... 

Yellow phosphorus ignites in molten ammonium nitrate, and mixtures of phosphorus with ammonium nitrate, mercuiy(I) nitrate or silver nitrate explode on impact. Red phosphorus is oxidised vigorously when heated with potassium nitrate [1]. During development of new refining agents for aluminium manufacture, a mixture containing red phosphorus (16%) and sodium nitrate (35%) was being pressed into 400 g tablets. When the die pressure was increased to 70 bar, a violent explosion occurred [2],... 

Before World War I, tbe main source of nitrates for human use was from large deposits of bird droppings in Peru and sodium nitrate from Chile. These sources were becoming scarce and expensive. Then Fritz Haber (1868-1934), a lecturer in a technical college in Germany, began to experiment with ways to manufacture ammonia. Haber knew that ammonia could he easily converted to nitrates and other useful nitrogen... 

Sodium bisulfate is a by-product of sodium sulfate manufacture. One process involves reacting sulfuric acid with sodium nitrate at high temperature to form nitric acid and sodium bisulfate ... 

Nitric acid Sodium nitrate, Sulfuric acid, Water Key component for many explosive manufacturing processes... 

The preparation of alkali carbonate from alkali nitrate.—The sodium nitrate required for the manufacture of nitric acid, and for the sulphuric acid chambers is converted into nitre-cake—sodium acid sulphate, and is utilized as salt-cake in making alkali. Many of the proposals for converting sodium nitrate into the carbonate, really aim at getting the alkali as a by-product in the manufacture of... 

Beside this basic method of manufacturing mercury fulminate, which is widely practised, there are alternate processes. Angelico [11] recognized that mercury fulminate is formed by treating a mercury solution in an excess of nitric acid with a concentrated aqueous solution of malonic acid in the presence of a small amount of sodium nitrate. The reaction results in a considerable rise of temperature, C02 evolution and the precipitation of the fulminate (L. W. Jones [12]). 

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. 

To a medium having a composition of 6.4 % of millet jelly, 0.5 % of glucose, 3.5 % of soybean powder, 0.75 % of corn steep liquor, 0.3 % of sodium chloride, 0.1 % of potassium secondary phosphate, 0.05 % of zinc sulfate, 0.01 % of copper sulfate, 0.2 % of sodium nitrate and 0.01 % of Toho No. 1 (trade name for a surface active agent composed of polyoxyethylene manufactured by Toho Chemical Industry Co. Ltd., Japan) was added 3-amino-propyl-dimethylsulfonium bromide hydrobromate in a proportion of 0.4 mg/ml to adjust the pH of the medium to 6.5. 

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 ... 

Potassium nitrate (saltpeter, KN03) is manufactured in two ways (1) by reacting nitric acid with potassium chloride with a chlorine by-product and (2) by reacting sodium nitrate with potassium chloride and crystallizing out the salt. 

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