Ammonium Nitrate

CAS RN:6484-52-2

Reactivities / Incompatibilities

With ammonium chloride, (barium nitrate), water, zinc: Addition of water to an intimate mixture of zinc powder and the salts causes spontaneous ignition and a mixture of ammonium nitrate and ammonium chloride...sprinkled with zinc dust ignites vigorously when moistened.

Mixtures of ammonium nitrate with charcoal and metal oxides: The pelleted explosive ("ammonpulver", containing 10% charcoal) normally ignites at 160-165 deg C, but presence of rust, or copper or zinc oxides, lowers the temperature to 80-120 deg C.

With fertilizer materials: Mixtures of ammonium nitrate, superphosphate and organic materials stored in bulk may ignite if the internal temperature exceeds 90 deg C. This is owing to the free acid in the superphosphate, and may be prevented by neutralization with ammonia.

During the flame cutting of a pipeline plugged with impure ammonium nitrate, the pipe contents exploded violently.

Fused ammonium nitrate with powdered metal is often a violent & sometimes an explosive reaction. Zinc, cadmium, copper, magnesium, lead, cobalt, nickel, bismuth, chromium, & antimony are the metals that reacted in this way.

A mixture of white (or yellow) phosphorus & ammonium nitrate can be exploded by percussion.

A mixture of ammonium sulfate and ammonium nitrate can easily be exploded by potassium or sodium-potassium alloy.

Sodium and ammonium nitrate react through a series of reductions to form a yellow explosive substance believed to be disodium nitrite.

The two substances /zinc and ammonium nitrate/ are mixed intimately and wetted with 3 or 4 drops of water. After a short time, a violent reaction occurs with the evolution of steam and zinc oxide.

Explodes more readily if contaminated with combustible /materials/.

With copper iron (II) sulfide: During preparations for blasting the sulfide mineral copper pyrites, ammonium nitrate based blasting cartridges exploded prematurely in the blast holes. This was attributed to exothermic interaction of acid groundwater with the sulfide-oxidant combination.

With metals: Shock sensitivity of mixtures of ammonium nitrate and powdered metals decreases in the order titanium, tin, aluminum, magnesium, zinc, lead, iron, antimony, and copper.

With urea: concentrated solutions of ammonium nitrate and urea exploded during large scale mixing operations. Although the cause was not established, hazards /associated with/ these operations are discussed in relation to the circumstances.

With potassium permanganate: Admixture of 0.5% potassium permanganate with an ammonium nitrate explosive caused an explosion 7 hr later. This was /due/ to formation and exothermic decomposition of ammonium permanganate leading to ignition.

Reacts violently with reducing agents, strong acids, powdered metals, organic materials.

A mixture of aluminum powder and ammonium nitrate can be used as an explosive. A number of explosions in which ammonium nitrate and aluminum are mixed with carbon, hydrocarbons, with or without oxidizing agents, have occured.

A mixture of ammonium nitrate and acetic acid ignites when warmed, especially if concentrated.

Explosions may occur when a mixture of /ammonium nitrate and carbon/ materials is heated.

Ammonium nitrate mixed with sulfur or with metal powders can be exploded by shock.

Ammonium nitrate of any grade, including fertilizer, when contaminated with oil, charcoal, or other organic materials should be considered an explosive capable of detonation by combustion or by explosion of adjacent explosive materials.

As ammonium nitrate solution becomes more acidic, its stability decreases, and it may be more likely to explode.

With Non-metals: the powdered salt in admixture with charcoal explodes at 170 deg C, or the sold salt on contact with glowing charcoal. Phosphorus ignites on the fused salt.

With trinitroanisole: A mixture of ammonium nitrate and 2,4,6-trinitroanisole, prepared as explosive by mixing the hot components, ignited spontaneously and exploded violently.

With Alkali metals: sodium progressively reduces the nitrate, eventually forming a yellow explosive solid, probably sodium hyponitrite.

Ammonium nitrate may also be sensitized by certain inorganic contaminants, including chlorides and some metals, such as aluminum powder, chromium, copper, cobalt, and nickel.

Ammonium nitrate mixed with oil or other sensitizing contaminants may explode or detonate when exposed to fire or shock. Organic materials (e.g., packing materials, seed, etc.) will increase the likelihood of an explosion and will make the ammonium nitate explosion more energetic.

Find more information on this substance at: Hazardous Substances Data Bank , TOXMAP , TOXNET , PubMed