Calcium ammonium nitrate

Last updated
Calcium ammonium nitrate
Names
Other names
CAN
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.035.702 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 239-289-5
PubChem CID
  • InChI=1S/Ca.HNO3.2NO3.H3N/c;3*2-1(3)4;/h;(H,2,3,4);;;1H3/q+2;;2*-1;
    Key: QGPZBKDRJAXSRG-UHFFFAOYSA-N
  • N.[N+](=O)(O)[O-].[N+](=O)([O-])[O-].[N+](=O)([O-])[O-].[Ca+2]
Properties
Variable
AppearanceWhite to Yellow crystals with similar shape to that of Ammonium nitrate
Related compounds
Related compounds
Ammonium nitrate
Calcium nitrate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Calcium ammonium nitrate or CAN, also known as nitro-limestone or nitrochalk, is a widely used inorganic fertilizer, accounting for 4% of all nitrogen fertilizer used worldwide in 2007. [1]

Contents

Production

The term "calcium ammonium nitrate" is applied to multiple different, but closely related formulations. One variety of calcium ammonium nitrate is made by adding powdered limestone to ammonium nitrate; [1] [2] another, fully water-soluble version, is a mixture of calcium nitrate and ammonium nitrate, which crystallizes as a hydrated double salt: [3] 5Ca(NO3)2•NH4NO3•10H2O. Unlike ammonium nitrate, [4] these calcium containing formulations are not classified as oxidizers by the United States Department of Transportation. [3]

Consumption of CAN was 3.54 million tonnes in 1973/74, 4.45 million tonnes in 1983/84, 3.58 million tonnes in 1993/94. [5] Production of calcium ammonium nitrate consumed 3% of world ammonia production in 2003. [5]

Physical and chemical properties

Calcium ammonium nitrate is hygroscopic. Its dissolution in water is endothermic, leading to its use in some instant cold packs.

Use

Most calcium ammonium nitrate is used as a fertilizer. Fertilizer grade CAN contains roughly 8% calcium and 21-27% nitrogen. [6] CAN is preferred for use on acid soils, [5] as it acidifies soil less than many common nitrogen fertilizers. [6] It is also used in place of ammonium nitrate where ammonium nitrate is banned. [2]

Calcium ammonium nitrate is used in some instant cold packs as an alternative to ammonium nitrate.

Calcium ammonium nitrate has seen use in improvised explosives. The CAN is not used directly, but is instead first converted to ammonium nitrate; "More than 85% of the IEDs used against U.S. forces in Afghanistan contain homemade explosives, and of those, about 70% are made with ammonium nitrate derived from calcium ammonium nitrate". [7] CAN and other fertilizers were banned in the Malakand Division and in Afghanistan following reports of its use by militants to make explosives. [8] Due to these bans, "Potassium chlorate — the stuff that makes matches catch fire — has surpassed fertilizer as the explosive of choice for insurgents." [9]

Related Research Articles

<span class="mw-page-title-main">Explosive</span> Substance that can explode

An explosive is a reactive substance that contains a great amount of potential energy that can produce an explosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. An explosive charge is a measured quantity of explosive material, which may either be composed solely of one ingredient or be a mixture containing at least two substances.

<span class="mw-page-title-main">Nitrate</span> Polyatomic ion (NO₃, charge –1) found in explosives and fertilisers

Nitrate is a polyatomic ion with the chemical formula NO
3
. Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insoluble nitrate is bismuth oxynitrate.

<span class="mw-page-title-main">Fertilizer</span> Substance added to soils to supply plant nutrients for a better growth

A fertilizer or fertiliser is any material of natural or synthetic origin that is applied to soil or to plant tissues to supply plant nutrients. Fertilizers may be distinct from liming materials or other non-nutrient soil amendments. Many sources of fertilizer exist, both natural and industrially produced. For most modern agricultural practices, fertilization focuses on three main macro nutrients: nitrogen (N), phosphorus (P), and potassium (K) with occasional addition of supplements like rock flour for micronutrients. Farmers apply these fertilizers in a variety of ways: through dry or pelletized or liquid application processes, using large agricultural equipment or hand-tool methods.

<span class="mw-page-title-main">Potassium nitrate</span> Chemical compound

Potassium nitrate is a chemical compound with a sharp, salty, bitter taste and the chemical formula KNO
3
. It is an ionic salt of potassium ions K+ and nitrate ions NO3, and is therefore an alkali metal nitrate. It occurs in nature as a mineral, niter (or nitre in the UK). It is a source of nitrogen, and nitrogen was named after niter. Potassium nitrate is one of several nitrogen-containing compounds collectively referred to as saltpeter (or saltpetre in the UK).

<span class="mw-page-title-main">Ammonium nitrate</span> Chemical compound with formula NH4NO3

Ammonium nitrate is a chemical compound with the formula NH4NO3. It is a white crystalline salt consisting of ions of ammonium and nitrate. It is highly soluble in water and hygroscopic as a solid, although it does not form hydrates. It is predominantly used in agriculture as a high-nitrogen fertilizer.

<span class="mw-page-title-main">ANFO</span> Explosive

ANFO ( AN-foh) (or AN/FO, for ammonium nitrate/fuel oil) is a widely used bulk industrial explosive. It consists of 94% porous prilled ammonium nitrate (NH4NO3) (AN), which acts as the oxidizing agent and absorbent for the fuel, and 6% number 2 fuel oil (FO). The use of ANFO originated in the 1950s.

<span class="mw-page-title-main">Potassium chlorate</span> Chemical compound

Potassium chlorate is a compound containing potassium, chlorine and oxygen, with the molecular formula KClO3. In its pure form, it is a white crystalline substance. After sodium chlorate, it is the second most common chlorate in industrial use. It is a strong oxidizing agent and its most important application is in safety matches. In other applications it is mostly obsolete and has been replaced by safer alternatives in recent decades. It has been used

<span class="mw-page-title-main">Plant nutrition</span> Study of the chemical elements and compounds necessary for normal plant life

Plant nutrition is the study of the chemical elements and compounds necessary for plant growth and reproduction, plant metabolism and their external supply. In its absence the plant is unable to complete a normal life cycle, or that the element is part of some essential plant constituent or metabolite. This is in accordance with Justus von Liebig's law of the minimum. The total essential plant nutrients include seventeen different elements: carbon, oxygen and hydrogen which are absorbed from the air, whereas other nutrients including nitrogen are typically obtained from the soil.

UAN is a solution of urea and ammonium nitrate in water used as a fertilizer. The combination of urea and ammonium nitrate has an extremely low critical relative humidity and can therefore only be used in liquid fertilizers. The most commonly used grade of these fertilizer solutions is UAN 32.0.0 (32%N) known as UN32 or UN-32, which consists of 45% ammonium nitrate, 35% urea and only 20% water. Other grades are UAN 28, UAN 30 and UAN 18. The solutions are quite corrosive towards mild steel and are therefore generally equipped with a corrosion inhibitor to protect tanks, pipelines, nozzles, etc. Urea–ammonium nitrate solutions should not be combined with calcium ammonium nitrate (CAN-17) or other solutions prepared from calcium nitrate. A thick, milky-white insoluble precipitate forms that may plug nozzles.

The nitrophosphate process is a method for the industrial production of nitrogen fertilizers invented by Erling Johnson in the municipality of Odda, Norway around 1927.

Sprengel explosives are a generic class of materials invented by Hermann Sprengel in the 1870s. They consist of stoichiometric mixtures of strong oxidisers and reactive fuels, mixed just prior to use in order to enhance safety. Either the oxidiser or the fuel, or both, should be a liquid to facilitate mixing, and intimate contact between the materials for a fast reaction rate.

<span class="mw-page-title-main">Silver fulminate</span> High explosive used in bang snaps

Silver fulminate (AgCNO) is the highly explosive silver salt of fulminic acid.

<span class="mw-page-title-main">Agricultural lime</span> Soil additive containing calcium carbonate and other ingredients

Agricultural lime, also called aglime, agricultural limestone, garden lime or liming, is a soil additive made from pulverized limestone or chalk. The primary active component is calcium carbonate. Additional chemicals vary depending on the mineral source and may include calcium oxide. Unlike the types of lime called quicklime and slaked lime, powdered limestone does not require lime burning in a lime kiln; it only requires milling. All of these types of lime are sometimes used as soil conditioners, with a common theme of providing a base to correct acidity, but lime for farm fields today is often crushed limestone. Historically, liming of farm fields in centuries past was often done with burnt lime; the difference is at least partially explained by the fact that affordable mass-production-scale fine milling of stone and ore relies on technologies developed since the mid-19th century.

<span class="mw-page-title-main">Ammonium sulfate</span> Chemical compound

Ammonium sulfate (American English and international scientific usage; ammonium sulphate in British English); (NH4)2SO4, is an inorganic salt with a number of commercial uses. The most common use is as a soil fertilizer. It contains 21% nitrogen and 24% sulfur.

<span class="mw-page-title-main">Calcium nitrate</span> Chemical compound

Calcium nitrate are inorganic compounds with the formula Ca(NO3)2(H2O)x. The anhydrous compound, which is rarely encountered, absorbs moisture from the air to give the tetrahydrate. Both anhydrous and hydrated forms are colourless salts. Hydrated calcium nitrate, also called Norgessalpeter (Norwegian salpeter), is mainly used as a component in fertilizers, but it has other applications. Nitrocalcite is the name for a mineral which is a hydrated calcium nitrate that forms as an efflorescence where manure contacts concrete or limestone in a dry environment as in stables or caverns. A variety of related salts are known including calcium ammonium nitrate decahydrate and calcium potassium nitrate decahydrate.

<span class="mw-page-title-main">Ammonium chlorate</span> Chemical compound

Ammonium chlorate is an inorganic compound with the formula NH4ClO3.

A pyrotechnic composition is a substance or mixture of substances designed to produce an effect by heat, light, sound, gas/smoke or a combination of these, as a result of non-detonative self-sustaining exothermic chemical reactions. Pyrotechnic substances do not rely on oxygen from external sources to sustain the reaction.

<span class="mw-page-title-main">Victor A. Tiedjens</span>

Victor Alphons Tiedjens (1895–1975) was an American horticulturist, agronomist, biochemist and soil chemist. He was credited as "one of the pioneers in growing plants in chemical solutions."

Many countries have standardized the labeling of fertilizers to indicate their contents of major nutrients. The most common labeling convention, the NPK or N-P-K label, shows the amounts of the chemical elements nitrogen, phosphorus, and potassium.

Seventeen elements or nutrients are essential for plant growth and reproduction. They are carbon (C), hydrogen (H), oxygen (O), nitrogen (N), phosphorus (P), potassium (K), sulfur (S), calcium (Ca), magnesium (Mg), iron (Fe), boron (B), manganese (Mn), copper (Cu), zinc (Zn), molybdenum (Mo), nickel (Ni) and chlorine (Cl). Nutrients required for plants to complete their life cycle are considered essential nutrients. Nutrients that enhance the growth of plants but are not necessary to complete the plant's life cycle are considered non-essential, although some of them, such as silicon (Si), have been shown to improve nutrent availability, hence the use of stinging nettle and horsetail macerations in Biodynamic agriculture. With the exception of carbon, hydrogen and oxygen, which are supplied by carbon dioxide and water, and nitrogen, provided through nitrogen fixation, the nutrients derive originally from the mineral component of the soil. The Law of the Minimum expresses that when the available form of a nutrient is not in enough proportion in the soil solution, then other nutrients cannot be taken up at an optimum rate by a plant. A particular nutrient ratio of the soil solution is thus mandatory for optimizing plant growth, a value which might differ from nutrient ratios calculated from plant composition.

References

  1. 1 2 Smil, Vaclav (2004). Enriching the Earth. Massachusetts Institute of Technology. p. 135. ISBN   9780262693134.
  2. 1 2 United Nations Industrial Development Organization (1998). Fertilizer Manual. Netherlands: Kluwer Academic. ISBN   9780792350323.
  3. 1 2 Yara Calcinit Technical Data [ permanent dead link ]
  4. 172.101 Hazardous Materials Table
  5. 1 2 3 Maxwell, Gary R. (2004). Synthetic Nitrogen Products. Kluwer Academic. p.  251. calcium ammonium nitrate.
  6. 1 2 Australian Soil Fertility Manual. Fertilizer Industry Federation of Australia. 2006. ISBN   9780643090217.
  7. Indiana nitrogen fertilizer plant on hold over link to bombs in Afghanistan
  8. Brummit, Chris (31 August 2011). "Pakistani fertilizer fuels Afghan bombs, US troop deaths". NBC. Retrieved 3 May 2013.
  9. Potassium chlorate — the stuff that makes matches catch fire — has surpassed fertilizer as the explosive of choice for insurgents.