Brief Introduction
Ammonium nitrate, is a colorless rhombic or monoclinic crystal at room temperature. It can be decomposed into water and nitrous oxide at 210 ° C. Upon severe heating at 300 ℃ above, it is subject to decomposition into nitrogen, oxygen and water. It is soluble in water, methanol and ethanol. It dissolution in water can absorb a lot of heat and reduce the temperature. It is one of the major nitrogen fertilizer varieties in the world today, accounting for about 3.5% of the total amount of nitrogen fertilizer in our country. The nitrogen form is nitrate, which belongs to the nitrate nitrogen fertilizer. In fact, ammonium nitrate both nitrate and ammonium nitrogen, but its nature is more similar to the nitrate nitrogen fertilizer.
Ammonium nitrate has no residue in the soil; and can be all absorbed by crops; being a physiological neutral fertilizer. Ammonium nitrate is suitable for a wide range of soils and crops but is most suitable for dry and dry crops especially suitable for cash crops such as tobacco, cotton and vegetables.
Ammonium nitrate should not be used as a basal fertilizer, because ammonium nitrate, after being applied to the soil, has its dissociated nitrate ions be easily leached into the soil. At the same time, ammonium nitrate should not be used seed manure because of its higher nutrient content, high hygroscopicity, which will affect the germination upon contact with seeds.
Ammonium nitrate, when applied in paddy field, can have its nitrogen content easily leached. Therefore, its efficiency is not comparable to other nitrogenous fertilizers of equal nitrogen content, being only equivalent to 50% -70% of that of ammonium sulfate with equal nitrogen content. The most ideal application is for topdressing, and is most suitable for top-dressing in dry land. The usage amount can be determined according to soil fertility and yield indicators. Should pay attention to the following points:
- Do not mix with acid fertilizers (such as superphosphate) and alkaline fertilizers (such as ash, etc.) to prevent the reduction of fertilizer efficiency.
- In the event of caking, gently crush it with sticks; avoid fiercely crushing it to prevent explosion.
- Apply sealed packaging, pay attention to moisture, heat; store way from combustibles and oxidants.
Chemical Properties
Ammonium nitrate (AN) is an odorless, colorless or white, crystal salt produced by the reaction of ammonia and nitric acid. It was the first solid nitrogen (N) fertilizer produced on a large scale. It has been a common nitrogen source because it contains both nitrate and ammonium, and has a relatively high nutrient content. For some crops it is the most environmentally and economically viable N fertilizer.
Uses
Ammonium nitrate can be used directly or as an important component of many fertilizer mixtures. It provides a source of nitrogen to plants to increase growth and crop yields. Ammonium nitrate is a popular fertilizer since it provides half of the N in nitrate form and half in ammonium form. The nitrate form moves readily with soil water to the roots where it is immediately available for plant uptake. Ammonium nitrate is more popular than other nitrogen fertilizers for pasture and hay fertilization since it is less susceptible to volatilization or air losses when left on the soil. It is also valued by vegetable growers for its ability to provide an immediately available nitrate source of plant food.
Agricultural Use
Since plant roots do not directly absorb the urea form of N to a large extent, ammonium nitrate is an efficient and immediate source of plant nutrition. It provides half of the N in the nitrate form and half in the ammonium form. The nitrate form is mobile in the soil water and immediately available for plant uptake. The ammonium fraction is taken up if roots grow nearby or after it is converted to nitrate by soil microorganisms during nitrification.
Many farmers prefer an immediately available nitrate source for plant nutrition and choose ammonium nitrate as their N fertilizer. It is popular for pasture and broad acre crops since almost no ammonia volatilization losses occur, compared to urea-based fertilizers. Some 37 million metric tons (MMt) of fertilizer grade ammonium nitrate are consumed worldwide annually in agriculture, of which about 14 MMt are used as CAN. Because of its high crop recovery, its ease of use, and its suitability for in-season top dressing, ammonium nitrate is widely used, especially in many European countries.
Production
The manufacture of ammonium nitrate involves several major unit operations including solution formation and concentration; solids formation, finishing, screening, and coating; and product bagging and/or bulk shipping. In some cases, solutions may be blended for marketing as liquid fertilizers.
The number of operating steps employed depends on the end product desired. For example, plants producing ammonium nitrate solutions alone use only the solution formation, solution blending, and bulk shipping operations. Plants producing a solid ammonium nitrate product may employ all of the operations.
All ammonium nitrate plants produce an aqueous ammonium nitrate solution through the reaction of ammonia and nitric acid in a neutralizer as follows:
NH3+HNO3 → NH4NO3
Approximately 60 percent of the ammonium nitrate produced in the U. S. is sold as a solid product. To produce a solid product, the ammonium nitrate solution is concentrated in an evaporator or concentrator. The resulting "melt" contains about 95 to 99.8 percent ammonium nitrate at approximately 149°C (300°F). This melt is then used to make solid ammonium nitrate products.
Extremely Insensitive Explosives
Ammonium nitrate is an extremely insensitive explosive that is more detrimental than the safe explosives c4. An industrial 8 # detonator (detonated c4 just 6 # on it) are not enough to detonate a mixture of sensitizer ammonium nitrate. Ammonium nitrate is the most detonating nitric acid explosives with impact sensitivity being: 50kg hammer with 50cm drop height will not cause explosion. The impact sensitivity of the famous explosive nitroglycerin: 200 g hammer at 20cm high drop height will lead to 100% explosion. And once the ammonium nitrate is dissolved in water, the detonation sensitivity is greatly reduced, for which it is impossible to detonate the ammonium nitrate with human power.
potential hazards
Ammonium nitrate readily attracts moisture from the air, and for this reason, is often stored in air-conditioned warehouses or in sealed bags. Ammonium nitrate is considered non-flammable; a fire from ammonium nitrate is very unlikely. However, it is a strong oxidizing agent that can cause combustible materials (such as wood, paper and oil) to ignite. Only under extreme conditions of heat and pressure in a confined space will ammonium nitrate explode.
Description
Ammonium nitrate is an oxidizer, which may explode under confinement and high temperatures. When mixed with fuel oil, a deflagrating explosive material is created. Ammonium nitrate and fuel oil were used as the explosive in the Alfred P. Murrah Federal Building terrorist attack in Oklahoma City and the first terror attack on the World Trade Center in New York City in the mid-1990s.
Chemical Properties
Ammonium nitrate,NH4N03, is a colorless crystalline solid existing in two forms, Between 16 and 32°C, the crystals are tetragonal; between 32 and 84 DC, the crystals are rhombic. The melting point of NH4N03 is 169.6 DC, and it decomposes above 210°C. When heated, ammonium nitrate yields nitrous oxide gas. Ammonium nitrate is soluble in water, in acetic acid solutions containing ammonia, is slightly soluble in ethanol, and is moderately soluble in methanol.
Ammonium nitrate is a very insensitive and stable high explosive used as a slow-burning propellant for rockets when compounded with burning rate catalysts. Although the major applications of Ammonium nitrate are explosives and fertilizers, it is also used in insecticides, rust inhibitors, and pyrotechnics.
Uses
Ammonium nitrate (NH4NO3, also known as “Norway saltpeter”) is mainly used as a fertilizer.
It is also known as the chemical that was mixed with diesel fuel to create the explosion
that demolished the Murrah Federal Building in Oklahoma City in 1995.
Uses
Colorless crystals made by the action of ammonium hydroxide
on nitric acid. Soluble in water, alcohol, and alkalies, ammonium
nitrate is explosive and was used as a substitute for
potassium nitrate in making flashlight mixtures.
Uses
Sold in a concentration of 27,5% N. Attributes Distributed by Agroline CH. Contact
Uses
Making nitrous oxide (laughing gas); in freezing mixtures, safety explosives, matches; pyrotechnics; in fertilizers.
Definition
ammonium nitrate: A colourlesscrystalline solid, NH
4NO
3; r.d. 1.72;m.p. 169.6°C; b.p. 210°C. It is verysoluble in water and soluble inethanol. The crystals are rhombicwhen obtained below 32°C andmonoclinic above 32°C. It may bereadily prepared in the laboratory bythe reaction of nitric acid with aqueousammonia. Industrially, it is manufacturedby the same reaction usingammonia gas. Vast quantities of ammoniumnitrate are used as fertilizers(over 20 million tonnes per year)and it is also a component of someexplosives.
Definition
ChEBI: The ammonium salt of nitric acid.
General Description
A colorless crystalline solid. Soluble in water. Does not readily burn but will do so if contaminated with combustible material. Accelerates the burning of combustible material. Produces toxic oxides of nitrogen during combustion. Used to make fertilizers and explosives, and as a nutrient in producing antibiotics and yeast.
Air & Water Reactions
Water soluble. Hot aqueous solutions of the nitrate above 50% conc., under confinement may decompose explosively. This process is aided catalytically with such substances as nitric acid and chloride ion, [Chem. Abs., 1982, 97, 78074].
Reactivity Profile
The hazards of AMMONIUM NITRATE have been well studied because of several extremely severe explosions [Chem. Eng., 1962, 70, 91; Bretherick, 5th Ed., 1995]. Mixtures with alkyl esters may explode, owing to the formation of alkyl nitrates. Mixtures with phosphorus, tin(II) chloride or other reducing agents may react explosively [Bretherick 1979 p. 108-109]. A mixture with aluminum powder (also zinc, cadmium, copper, magnesium, lead, cobalt, nickel, bismuth, chromium, and antimony) can be used as an explosive. A number of explosions in which ammonium nitrate and aluminum were mixed with carbon or hydrocarbons, with or without oxidizing agents have occurred [Mellor 5:219 1946-47]. A mixture with acetic acid ignites when warmed, especially if concentrated [Von Schwartz p. 322 1918]. Causes the decomposition of sodium hypochlorite within a few seconds [Mellor 2 Supp. 1:550 1956].
Hazard
May explode under confinement and high temperatures, but not readily detonated. Ventilate well. To fight fire, use large amounts of water. The material must be kept as cool as possible and removed from confinement and flooded with water in event of fire.
Health Hazard
Inhalation, ingestion or contact (skin, eyes) with vapors or substance may cause severe injury, burns or death. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may cause pollution.
Fire Hazard
These substances will accelerate burning when involved in a fire. Some may decompose explosively when heated or involved in a fire. May explode from heat or contamination. Some will react explosively with hydrocarbons (fuels). May ignite combustibles (wood, paper, oil, clothing, etc.). Containers may explode when heated. Runoff may create fire or explosion hazard.
Flammability and Explosibility
Non flammable
Agricultural Uses
Ammonium nitrate (NH
4NO
3) is among the most
common nitrogenous fertilizers, with half of its nitrogen
in an ammoniacal form and the rest in nitrate form.
The nitrogen from ammonium nitrate is immediately
available to plants, whereas the ammoniacal nitrogen
becomes available only after its nitration. Fertilizer grade
ammonium nitrate solution in water containing 20%
nitrogen is sold in large quantities, because of its high
water solubility and easy soil applicability. The fertilizer
can also be used in its compound forms, such as calcium
ammonium nitrate and ammonium sulphate nitrate.
The nitrogen in ammonium nitrate is more rapidly
available than that in urea or ammonium sulphate. Crops
take up nitrogen mainly in the form of nitrate. The
ammoniacal nitrogen must be converted to nitrate in the
soil before it becomes effective. Urea causes seedling
damage due to volatilization of ammonia. Ammonium
nitrate and ammonium sulphate are strongly acidforming
fertilizers.
Although pure salt ammonium nitrate is a fine white
crystal, it is usually available as white granules or prills
of 1.2 to 3.3 mm size and contains 32 to 35 % nitrogen by
weight. The crystalline form is highly hygroscopic and is
readily soluble in water. Because of this high solubility in
water, it is less effective for flooded rice than urea or
other ammoniacal nitrogen fertilizers. It is also more
prone to leaching than other ammoniacal products. It is
also a very powerful oxidizing agent which can explode
when exposed to heat or flame. Because of this hazardous
property, ammonium nitrate and its compounds are
stored in a dry place in sealed bags. The granular form,
however, is easily stored. It can also be spread on soil
with ease.
Ammonium nitrate, like other ammonium
fertilizers, can leave behind an acid residue in the soil. It
takes 0.8 kg of lime to neutralize the acidity produced by
1 kg of ammonium nitrate fertilizer.
Ammonium nitrate and urea are the most widely used
sources of nitrogen from among all solid fertilizers
available. A two bale crop of cotton removes 56 kg of
nitrogen per hectare in the seed alone and 16.8 kg of
nitrogen per hectare in the lint. To supply this amount of
nitrogen, the addition of 224 kg per hectare of ammonium
nitrate is required. A 2240 kg per hectare tobacco crop
removes 123 kg of nitrogen per hectare, and 5600 kg per
hectare crop of rice removes 90 kg of nitrogen per
hectare.
Ammonium nitrate is used as a major source of
nitrogen for crops in the USA. It is a good nitrogen plant
food for all field and vegetable crops and can be applied
to the soil before or at the time of planting. It also makes
for a good N-fertilizer for side dressing or top dressing.
An aqueous solution of urea and ammonium nitrate,
called UAN is used as a liquid nitrogen fertilizer.
‘Ammonite’ is a trademark for a mixture of ammonium
nitrate (98%) and coating agents (2%).
Safety Profile
A powerful oxidizer
and an allergen. See also NITRATES. A
relatively stable explosive that has, however,
caused many industrial explosions. Violent
or explosive spontaneous reactions with
acetic anhydride + nitric acid, ammonium
sulfate + potassium, copper iron(Ⅱ) sulfide,
sawdust, urea, barium nitrate, hot water, and
ammonium chloride + water + zinc. Forms
heator shock-sensitive explosive mixtures
with acetic acid, aluminum + calcium nitrate
+ formamide (a blasting explosive),
ammonia, charcoal + metal oxides (e.g., rust,
copper oxide, zinc oxide above 80℃),
chloride salts (e.g., ammonium chloride,
calcium chloride, iron(ⅡI) chloride, and
aluminum chloride), cyanoguanidine,
feruH2ers (e.g., super phosphate + organic
materials above 90℃), hydrocarbon oils,
powdered metals (e.g., aluminum, antimony,
bismuth, cadmium, chromium, cobalt,
copper, iron, lead, magnesium, manganese,
nickel, tin, zinc, brass, stainless steel,
titanium, and potassium), nonmetals (e.g.,
charcoal, and phosphorus), organic fuels
(e.g., wax, oils, and stearates), potassium
permanganate, sugar, sulfur, and
trinitroanisole. Reaction with alkali metals
(e.g., sodium) forms an explosive product.
Ignites on contact with ammonium
dichromate, potassium dichromate,
potassium chromate, barium chloride,
sodium chloride, potassium nitrate, and
chromium(V1) salts. Can ignite when mixed
with acetic acid. Use water in large amounts
to fight fire. It is important that the mass of
materials be kept cool and that burning be
extinguished promptly. Ventilate well. May
explode under confinement and high temperatures. When heated to
decomposition it emits highly toxic fumes of NOx. Can react vigorously with reducing
materials. Incompatible with, (NH4Cl +
heat), (C + heat), organic matter, P, NaOCl,
NaClO4. Occasional explosions in presence
of oil, (NH4)2S04 with K or Na.
Potential Exposure
Used in the manufacture of liquid and
solid fertilizer compositions, industrial explosives and
blasting agents from ammonium nitrate, matches; antibiotics;
in the production of nitrous oxide.
Metabolism
Ammonium Nitrate. Ammonium nitrate is one of the
two leading nitrogen fertilizer materials on a world basis:
10% in 1997. The high N content is advantageous for the
reduction of freight and application costs per unit weight
of nitrogen. The presence of 50% of the nitrogen in the
highly available nitrate form makes it suitable for use
in regions growing crops with a short vegetation period
but has the disadvantage that, because the NO3
? ion is
not adsorbed by soil, it may contribute to relatively large
nitrogen losses by the leaching of increased soil nitrate
into streams and groundwater. Although the application
of any nitrogenous fertilizer results in some degree of soil
acidification, the nitrate form is notably less acidifying
than ammonium sulfate and has a lower tendency for the
loss of nitrogen to the atmosphere as gaseous ammonia.
The hygroscopic character of the crystalline material,
coupled with its explosive nature, contributes to difficult
storage and handling properties and the need for the
production of purified and stabilized forms.
Shipping
Ammonium nitrate with organic coating:
UN0222 Ammonium nitrate, with . 0.2% combustible
substances, including any organic substance calculated as
carbon, to the exclusion of any other added substance,
Hazard Class: 1D; Labels:1D-Explosive (with a mass
explosion hazard); D-Substances or articles which may mass detonate (with blast and/or fragment hazard) when
exposed to fire. Ammonium nitrate with NO organic coating:
UN1942 Ammonium nitrate, with NOT . 0.2% of
combustible substances, including any organic substance
calculated as carbon, to the exclusion of any other added
substance (also used for fertilizer), Hazard Class: 5.1;
Labels: 5.1-Oxidizer. UN3375 Ammonium nitrate emulsion
or Ammonium nitrate suspension or Ammonium
nitrate gel, intermediate for blasting explosives, Hazard
Class: 5.1; Labels: 5.1-Oxidizer. UN2072 Ammonium
nitrate fertilizer, n.o.s., doesn’t appear in the 49 CFR
Hazmat Table, refer to UN1942, above). UN2071
Ammonium nitrate based fertilizer, Hazard class: 9;
Labels: 9-Miscellaneous hazardous material. UN2426/140
Ammonium nitrate, liquid (hot concentrated solution),
Hazard Class: 5.1; Labels: 5.1-Oxidizer.
Purification Methods
It is crystallised twice from distilled water (1mL/g) by adding EtOH, or from warm water (0.5mL/g) by cooling in an ice-salt bath. Dry it in air, then under vacuum. After 3 recrystallisations of ACS grade, it contained Li and B at 0.03 and 0.74 ppm, respectively. It is deliquescent. [Early & Lowry J Chem Soc 115 1387 1919, 121 963 1922, Hendricks et al. J Am Chem Soc 54 2766 1932.]
Incompatibilities
A strong oxidizer. Reducing agents;
combustible materials; organic materials; finely divided
(powdered) metals may form explosive mixtures or cause
fire and explosions. When contaminated with oil, charcoal
or flammable liquids, can be considered an explosive which
can be detonated by combustion or shock.
Waste Disposal
Pretreatment involves addition
of sodium hydroxide to liberate ammonia and form the
soluble sodium salt. The liberated ammonia can be recovered
and sold. After dilution to the permitted provisional
limit, the sodium salt can be discharged into a stream or
sewer.
