Ammonium perchlorate

Production

Ammonium perchlorate (AP) is produced by reaction between ammonia and perchloric acid. This process is the main outlet for the industrial production of perchloric acid. The salt also can be produced by salt metathesis reaction of ammonium salts with sodium perchlorate. This process exploits the relatively low solubility of , which is about 10% of that for sodium perchlorate.

AP crystallises as colorless rhombohedra.

Decomposition

Like most ammonium salts, ammonium perchlorate decomposes before melting: : The combustion of AP is quite complex and is widely studied. AP crystals decompose before melting, even though a thin liquid layer has been observed on crystal surfaces during high-pressure combustion processes. Strong heating may lead to explosions. Complete reactions leave no residue. Pure crystals cannot sustain a flame below the pressure of 2 MPa.

AP is a Class 4 oxidizer (can undergo an explosive reaction) for particle sizes over 15 micrometres and is classified as an explosive for particle sizes less than 15 micrometres.

Applications

The primary use of ammonium perchlorate is in making solid rocket propellants. When AP is mixed with a fuel (like a powdered aluminium and/or with an elastomeric binder), it can generate self-sustained combustion at pressures far below atmospheric pressure. It is an important oxidizer with a decades-long history of use in composite rocket propellants (including the Space Shuttle Solid Rocket Booster), military, amateur, and hobbyist high-power rockets, as well as in some fireworks.

Toxicity

Perchlorate itself confers little acute toxicity. For example, sodium perchlorate has an of 2–4g/kg and is eliminated rapidly after ingestion. However, chronic exposure to perchlorates, even in low concentrations, has been shown to cause various thyroid problems, as it is taken up in place of iodine.

References

References

1. [https://www.sigmaaldrich.com/US/en/product/sial/208507 MSDS]. sigmaaldrich.com.
2. (18 June 2018). "CRC Handbook of Chemistry and Physics". CRC Press.
3. (2004). "Effects of Nanometer Ni, Cu, Al and NiCu Powders on the Thermal Decomposition of Ammonium Perchlorate". [[Propellants, Explosives, Pyrotechnics]].
4. (11 February 1998). "NIST-JANAF Themochemical Tables, Fourth Edition".
5. Helmut Vogt, Jan Balej, John E. Bennett, Peter Wintzer, Saeed Akbar Sheikh, Patrizio Gallone "Chlorine Oxides and Chlorine Oxygen Acids" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH. {{doi. 10.1002/14356007.a06_483
6. (1970). "Deflagration Rate, Surface Structure and Subsurface Profile of Self-Deflagrating Single Crystals of Ammonium Perchlorate". AIAA Journal.