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'''Ammonium perchlorate''' is an [[inorganic compound]] with the formula [[Nitrogen|N]][[Hydrogen|H]]<sub>4</sub>[[Chlorine|Cl]][[Oxygen|O]]<sub>4</sub>. It is the [[Salt (chemistry)|salt]] of [[perchloric acid]] and [[ammonia]]. It is a powerful [[oxidizer]], which is why its main use is in solid [[propellant]]s. It has been implicated in a number of accidents, such as the PEPCON industrial disaster and the Apartheid-era crash of South African Airways Flight 295.
'''Ammonium perchlorate''' is an [[inorganic compound]] with the formula [[Nitrogen|N]][[Hydrogen|H]]<sub>4</sub>[[Chlorine|Cl]][[Oxygen|O]]<sub>4</sub>. It is the [[Salt (chemistry)|salt]] of [[perchloric acid]] and [[ammonia]]. It is a powerful [[oxidizer]], which is why its main use is in solid [[propellant]]s. It has been implicated in a number of accidents, such as the PEPCON industrial disaster and the Apartheid-era crash of [[South African Airways Flight 295]].


==Production==
==Production==

Revision as of 14:29, 7 July 2013

Ammonium perchlorate
Ammonium perchlorate
Unit cell of the crystal structure
Names
IUPAC name
Ammonium perchlorate
Other names
AP
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.029.305 Edit this at Wikidata
EC Number
  • 232-235-1
RTECS number
  • SC7520000
UN number 1442
  • InChI=1S/ClHO4.H3N/c2-1(3,4)5;/h(H,2,3,4,5);1H3 checkY
    Key: HHEFNVCDPLQQTP-UHFFFAOYSA-N checkY
  • InChI=1/ClHO4.H3N/c2-1(3,4)5;/h(H,2,3,4,5);1H3
    Key: HHEFNVCDPLQQTP-UHFFFAOYAD
  • [O-]Cl(=O)(=O)=O.[NH4+]
Properties
NH4ClO4
Molar mass 117.49 g/mol
Appearance White Crystalline [1]
Density 1.95 g/cm3
Melting point Exothermic decomposition before melting at >200 °C[2]
11.56 g/100 mL (0 °C)
20.85 g/100 mL (20 °C)
57.01 g/100 mL (100 °C)
Solubility Soluble in Methanol
partially soluble in Acetone
insoluble in Ether
Structure
Orthorhombic (< 513 K)
Cubic (> 513 K)
Hazards
NFPA 704 (fire diamond)
Related compounds
Other anions
Ammonium chlorate
Ammonium chloride
Other cations
Potassium perchlorate
Sodium perchlorate
Lithium perchlorate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Ammonium perchlorate is an inorganic compound with the formula NH4ClO4. It is the salt of perchloric acid and ammonia. It is a powerful oxidizer, which is why its main use is in solid propellants. It has been implicated in a number of accidents, such as the PEPCON industrial disaster and the Apartheid-era crash of South African Airways Flight 295.

Production

Ammonium perchlorate (AP) is produced by reaction between ammonia and perchloric acid, and is the driver behind the industrial production of perchloric acid. It also can be prepared by treatment of ammonium salts with sodium perchlorate. This process exploits the fact that the solubility of NH4ClO4 is about 10% of that for sodium perchlorate.[4]

AP crystallises into colorless rhombohedra.

Decomposition

Like most ammonium salts, ammonium perchlorate decomposes before melting. Mild heating results in the evolution of chlorine, nitrogen, oxygen, and water.

2 NH4ClO4 → Cl2 + N2 + 2 O2 + 4 H2O

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.[5] 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[6] and is classified as an explosive for particle sizes less than 15 micrometres.[7][8]

Applications

The vast majority of ammonium perchlorate is used to make solid propellants.[9] When AP is mixed with a fuel (like a powdered aluminum and/or with an elastomeric binder), it can generate self-sustained combustion at far under atmospheric pressure. It is an important oxidizer with a decades-long history of use in solid rocket propellantsspace launch (including the Space Shuttle Solid Rocket Booster), military, amateur, and hobby high-power rockets, as well as in some fireworks.

Some "breakable" epoxy adhesives contain suspensions of AP. Upon heating to 300 °C, the AP degrades the organic adhesive, breaking the cemented joint.

Toxicity

Perchlorate itself confers little acute toxicity. For example, sodium perchlorate has an LD50 of 2-4 g/kg and is eliminated rapidly after ingestion.[4] 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.

See also

References

  1. ^ http://www.sigmaaldrich.com/MSDS/MSDS/DisplayMSDSPage.do?country=AE&language=en&productNumber=208507&brand=SIAL&PageToGoToURL=http%3A%2F%2Fwww.sigmaaldrich.com%2Fcatalog%2Fproduct%2Fsial%2F208507%3Flang%3Den Page 3, 9.1 (a)
  2. ^ Liu, L.; Li, F.; Tan, L.; Ming, L.; Yi, Y. (2004), "Effects of Nanometer Ni, Cu, Al and NiCu Powders on the Thermal Decomposition of Ammonium Perchlorate", Propellant, Explosives, Pyrotechnics, 29: 34–38, doi:10.1002/prep.200400026{{citation}}: CS1 maint: multiple names: authors list (link)
  3. ^ https://www.sciencelab.com/msds.php?msdsId=9922929
  4. ^ a b 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
  5. ^ T. L. Boggs, Deflagration Rate, Surface Structure and Subsurface Profile of Self-Deflagrating Single Crystals of Ammonium Perchlorate. AIAA Journal, 8(5), 1970, pp. 867--873.
  6. ^ NFPA 400: Hazardous Materials Code, 2010
  7. ^ NFPA 495: Explosive Materials Code, 2010
  8. ^ "Development of an Enhanced Hazard Classification System for Oxidizers Research Project, Technical Report", Safety Engineering Laboratories , Inc., The Fire Protection Research Foundation, 13 April 2006
  9. ^ "Perchlorate: Overview of Issues, Status, and Remedial Actions", ITRC, September 2005 accessed 4 July 2011