Ammonium Nitrate - Shoan

Abbreviation for ammonium nitrate (fertilizer). Main component NH ₄ NO ₃ , N = 32-34%. A type of nitrogen fertilizer. It is made by neutralizing ammonia and nitric acid under normal or pressurized pressure. In the normal pressure method, ammonia is added to 45% nitric acid. Part of the ammonium nitrate solution (65%), which is heated to 100-110°C by the heat of neutralization, is reused in the neutralization tank, and the rest is evaporated at a temperature of 135°C or less to concentrate it to 90%. In the pressurized method, the neutralization reaction is carried out by raising the boiling point of the nitric acid, and the temperature inside the tank is kept at 155°C and 4 atm using the heat of neutralization (Fauser method). The basic unit is 212 kg (100%) of ammonia and 1,480 kg (53%) of nitric acid per 1 ton of ammonium nitrate, and it has excellent fertilizer effectiveness. However, due to its high hygroscopicity and tendency to run off, it is not suitable for use in Japan, but it has become an important ingredient in compound fertilizers. It has been devised to prevent moisture, for example, by covering it with oil or fat, mixing it with lime to make ammonium nitrate lime, or adding ammonium sulfate to a hot concentrated solution of ammonium nitrate to make ammonium sulfate. It is colorless and has an orthorhombic crystal structure. It transforms into a tetragonal crystal structure at temperatures below -18°C, into another orthorhombic crystal structure at 32.1°C, into a tetragonal crystal structure at 84.2°C, and into a cubic crystal structure at 125°C. Its density is 1.725 g cm ^-3 . Its uses include nitrogen fertilizer and explosives raw material. [See other terms] Chemical fertilizer, compound fertilizer

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

硝酸アンモニウム(肥料)の略称．主成分NH₄NO₃，N ＝ 32～34％．窒素肥料の一つ．アンモニアと硝酸とを常圧または加圧下で中和してつくる．常圧式では45％ 硝酸にアンモニアを加える．中和熱で100～110 ℃ になる硝安液(65％)の一部を中和槽で再使用し，ほかを135 ℃ 以下の温度で蒸発して90％ に濃縮する．加圧式では硝酸の沸点上昇のもとで中和反応を行わせ，中和熱を利用して槽内温度を155 ℃，4 atm に保つ(Fauser式)．原単位は硝安1 t に対しアンモニア212 kg(100％)，硝酸1480 kg(53％)，肥効性はすぐれている．しかし，吸湿性と流亡性が大きいため，わが国では適さないが，配合肥料の成分として重要になった．防湿に工夫がなされ，油脂で覆ったり，石灰と混合して硝安石灰としたり，硫安(硫酸アンモニウム)を硝安の熱濃厚溶液に加えて硫硝安としている．無色，斜方晶．－18 ℃ 以下で正方晶，32.1 ℃ で別な斜方晶へ，84.2 ℃ で正方晶，125 ℃ で立方晶へと転移する．密度1.725 g cm^－3．用途は窒素肥料，爆薬原料など．[別用語参照]化学肥料，化成肥料

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