Currently nitric acid 98%-65% (HNO3) is used to produce industrial explosives. Since nitric acid 98%-65% is highly unstable and also due to the high cost of transportation, producing this acid with the mentioned concentrations cost a lot. Nowadays, with the development of the mining industry and the defense industry, the need to mass production of economical and inexpensive industrial explosives is deeply felt.
This project has decreased the expenses of the production of the industrial explosives such as T.N.T, T.N.G, P.E.T.N, T.N.C and O.N.S, up to one-tenth of the current expenses by removing nitric acid 98%-65% from the chemical reaction of adding NO2 to organic materials.
If the price, the volume and the method of production of one kilogram of the ammonium nitrate is compared with those of a liter of nitric acid 98%-65%, the value of this project will be industrially figured out. Furthermore, the product of this project, due to the decreased acid concentration, has a better quality compared to the product produced in the method of nitric acid 98%. The other benefit of using ammonium nitrate instead of nitric acid 98% is that the costs of transportation decreases and the maintenance duration and the safety increase.
Besides ammonium sulfate, a chemical fertilizer, is produced as a byproduct of this method and consequently, part of expenses is compensated. It must be mentioned that ammonium sulfate is not produced in common methods of producing explosives. In this project, there is no need to change systems and apparatus by which explosives are produced in nitric acid 98% method.
H2SO4+2 NH3→(NH4)2SO4/NH4HSO4+NH3→(NH4)2SO4
A brief description of parts has been introduced below:
9: Ammonium nitrate containing tank;
10: Sulfuric acid containing tank;
11: Container in which acid and ammonium nitrate are mixed and nitro ion (NO2) is produced;
12: The tank in which organic materials such as toluene, glycerin and etc. are stored.
13: The tank in which chemical reactions occur and explosives are produced. This tank also contains systems of controlling the temperature and the stirrers.
14: The tank in which PH is neutralized and the product is separated from acid, water, and ammonium sulfate.
Production of industrial explosives is one of the major subjects of studies in organic chemistry. In order to manufacture every kind of explosives, nitro (NO2) group must be added to the organic materials. These organic materials include toluene to produce TNT, glycerin to produce nitroglycerin and etc.
The most important raw material needed for the production of explosives is nitric acid in 98% concentration. However, this project aims at removing nitric acid 98% from the raw materials in order to highly reduce the production costs.
In the project of using nitrate salts, two chemical reactions are combined: the old method of producing nitric acid and the reaction of adding nitro (NO2) to the organic materials.
In the old method of producing nitric acid, three types of salt are used: ammonium nitrate (NH4NO3), potassium nitrate (KNO3) and sodium nitrate (NaNO3). Each of these three salts is separately combined with sulfuric acid (H2SO4) and nitric acid is produced; the related chemical reactions are showed as following (
NH4NO3+H2SO4→HNO3+NH4HSO4
KNO3+H2SO4→HNO3+KHSO4
NaNO3+H2SO4→HNO3+NaHSO4
The other chemical reaction which is used in this project is adding nitro (NO2) to the organic materials; in other words, the reaction of producing explosives.
In fact, the chemical reaction of producing explosives is the dehydration between nitric acid 98% (HNO3) and organic compounds (CxHy) such as toluene C6H5CH3, glycerin C3H5 (OH)3 and etc. This reaction happens through using sulfuric acid (H2SO4) as a catalyst. In this reaction, nitric acid releases a nitro group (NO2) and organic materials release hydrogen and this hydrogen reacts with hydroxyl group (OH) released from nitric acid and as a result, one molecule of water (H2O) is produced.
The related open and closed systems of these reactions are showed as following:
HONO2+H2SO4+CxHy→HOH+H2SO4+CxHy′NO2
HNO3+H2SO4+CxHy→H2O+H2SO4+CxHy′NO2
In this project, two chemical reactions, namely the traditional method to produce nitric acid and the reaction of adding nitro to organic materials, are combined and ammonium nitrate is used instead of nitric acid 98% in the second reaction. Ammonium nitrate (NH4NO3) is industrially produced in high volume as a chemical fertilizer. It also can be used to produce explosives due to having oxidation properties. However, since it is highly permeable and less sensitive and also due to some other problems, it cannot be a proper replacement for industrial explosives.
Ammonium nitrate is produced through the reaction between the diluted nitric acid 20%-40% and ammonia (NH3), which is a reaction between an acid and a base. Low concentrations of nitric acid reduce the production costs.
The reaction to produce ammonium nitrate is as following:
NH3+HNO3→NH4NO3
If ammonium nitrate is used in the reaction of producing explosives (i.e. adding nitro to organic materials), there will be no need to use nitric acid 98%; because when the solid ammonium nitrate is mixed with sulfuric acid, nitric acid 98% is produced in the reaction medium.
The overall objective of this project was using inexpensive nitric acid 40% in the reaction of producing industrial explosives. However, the chemical reaction of adding nitro to the organic materials is disrupted due to 60% water impurities in acid 40%. If ammonium nitrate is used, expenses will equal to the price of nitric acid 40% but in the reaction medium, nitric acid 98% is available. Therefore, there are no water molecules in raw materials and the dehydration reaction is very well done. Furthermore, ammonium nitrate has a little amount of impurities which does not disrupt the reaction. After the reaction and when the explosives are produced, these impurities are separated from the explosives through adding water to the solution (
Generally, the open and closed systems reactions of the production of explosives using nitrate salts (i.e. ammonium nitrate) are as following:
NH3HONO2+H2SO4+CxHy→HOH NH3H2SO4+CxHy′NO2
NH4NO3+H2SO4+CxHy→H2O+NH4HSO4+CxHy′NO2
In the above reactions, sodium nitrate, potassium nitrate or any other nitrate salts can be used instead of ammonium nitrate. However, if these salts are used, the project will not have industrial value, because these salts are not massively produced and due to having potassium, sodium and etc. they are expensive.
This project offers a general method to add the nitro group to a variety of organic materials (CxHy). In the chemical reaction, any organic material which has acid hydrogen can be used and the nitro group can be replaced with it. For instance, in this project, four types of industrial explosives are produced by using ammonium nitrate.
The related reactions are as following.
NH4NO3+3 H2SO4+C3H5 (OH)3→3 H2O+3 NH4HSO4+C3H5(NO3)3
The reaction of tri-nitrocellulose (T.N.C) production by using ammonium nitrate Physical form of the T.N.C is showed in the
3 NH4NO3+3 H2SO4+{C6H10O5}n→3 H2O+3 NH4HSO4+{C6H7O2(NO3)3}n
The reaction of tri-nitro-toluene (T.N.T) production by using ammonium nitrate Physical form of the T.N.T is showed in the
3 NH4NO3+3 H2SO4+C6H5CH3→3 H2O+3 NH4HSO4+C6H2CH3 (NO2)3
The reaction of octa-nitro-sucrose (O.N.S) production by using ammonium nitrate Physical form of the O.N.S is showed in the
8 NH4NO3+8 H2SO4+C12H22O11→8 H2O+8 NH4HSO4+C12H14O3 (NO3)8
Acid concentration decreases due to the use of ammonium nitrate in the reaction medium. Hence, the resulted product has a higher quality compared to the product of the conventional method of using nitric acid 98%. By comparing the transportation costs, maintenance durations, and the chemical stabilities of these two methods products, the industrial value of the project can be realized. Furthermore, in the method of using ammonium nitrate, there is no need to change systems and apparatus by which explosives are produced in nitric acid 98% method, because after ammonium nitrate is mixed with sulfuric acid, next production steps are the same as the nitric acid method.
In the
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For example, in order to produce nitroglycerin, the solution temperature must decrease up to 5 centigrade. Afterwards, the organic material (toluene, glycerin, sucrose, cellulose, or etc.) must be moved from the tank 12 to the tank 13 and mixed well by a mixing machine (the temperature must be under control). Finally, pure water is added to the solution, three times of the solution volume. Thus, the explosive that now is in organic phase and is not water-soluble will be separated from other materials and impurities. The last step is to send the produced explosive and sodium bicarbonate, to the tank 14 in order to neutralize the PH.