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Other names Ammonium peroxydisulfate | |
Identifiers | |
CAS Number | |
3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.028.897 |
EC Number |
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E number | E923 (glazing agents, ...) |
RTECS number |
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UNII | |
UN number | 1444 |
CompTox Dashboard (EPA) | |
InChI
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SMILES
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Properties | |
Chemical formula | (NH4)2S2O8 |
Molar mass | 228.18 g/mol |
Appearance | white to yellowish crystals |
Density | 1.98 g/cm |
Melting point | 120 °C (393 K) decomp. |
Solubility in water | 80 g/100 mL (25 °C) |
Hazards | |
NFPA 704 (fire diamond) | 2 0 2OX |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 689 mg/kg, oral (rat) |
Related compounds | |
Other anions | Ammonium thiosulfate Ammonium sulfite Ammonium sulfate |
Other cations | Sodium persulfate Potassium persulfate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). Y verify (what is ?) Infobox references |
Ammonium persulfate (APS) is the inorganic compound with the formula (NH4)2S2O8. It is a colourless (white) salt that is highly soluble in water, much more so than the potassium salt. It is a strong oxidizing agent that is used in polymer chemistry, as an etchant, and as a cleaning and bleaching agent.
The dissolution of the salt in water is endothermic. When APS dissolves in water, it is broken down into ammonia and peroxydisulfuric acid.
Preparation
Ammonium persulfate is prepared by electrolysis of a cold concentrated solution ammonium sulfate in sulfuric acid at a high current density. The method was first described by H. Marshall.
Uses
As an oxidizer and a source of radicals, APS finds many commercial applications.
Salts of peroxydisulfate are mainly used as radical initiators in the polymerization of certain alkene]]s. Commercially important polymers prepared using persulfates include styrene-butadiene rubber and polytetrafluoroethylene. In solution, the dianion dissociates to give radicals:
- 2
The sulfate radical adds to the alkene to give a sulfate ester radical. It is also used along with tetramethylethylenediamine to catalyze the polymerization of acrylamide in making a polyacrylamide gel.
It is used to etch copper on printed circuit boards as an alternative to ferric chloride solution. This property was discovered many years ago. In 1908, John William Turrentine used a dilute ammonium persulfate solution to etch copper. Turrentine weighed copper spirals before placing the copper spirals into the ammonium persulfate solution for an hour. After an hour, the spirals were weighed again and the amount of copper dissolved by ammonium persulfate was recorded. This experiment was extended to other metals such as nickel, cadium, and iron, all of which yielded similar results.
Ammonium persulfate is the main component of Nochromix, a laboratory cleaning agent. On dissolving in sulfuric acid, it is used to clean laboratory glassware as a metal-free alternative to chromic acid baths. It is also a standard ingredient in western blot gels and hair bleach.
Safety
Airborne dust may be irritating to eye, nose, throat, lung and skin upon contact. Exposure to high levels of dust may cause difficulty in breathing.
It has been noted that persulfate salts are a major cause of asthmatic effects in women. Furthermore, it has been suggested that exposure to ammonium persulfate can cause asthmatic effects in hair dressers and receptionists working in the hair dressing industry. These asthmatic affects are proposed to be caused by the oxidation of cysteine residues, as well as methionine residues.
References
- F. Feher, "Potassium Peroxydisulfate" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 390.
- Hugh Marshall (1891). "LXXIV. Contributions from the Chemical Laboratory of the University of Edinburgh. No. V. The persulphates". J. Chem. Soc., Trans. 59: 771. doi:10.1039/CT8915900771.
- Harald Jakob, Stefan Leininger, Thomas Lehmann, Sylvia Jacobi, Sven Gutewort. "Peroxo Compounds, Inorganic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a19_177.pub2. ISBN 978-3527306732.
{{cite encyclopedia}}
: CS1 maint: multiple names: authors list (link) - "Ammonium Persulphate: Copper Etchant". MG Chemicals.
- Turrentine, J. W. (1908). "Action of Ammonium Persulphate on Metals". Journal of Physical Chemistry. 11: 623–631.
- "Nochromix". Sigma-Aldrich. Retrieved 2008-03-01.
- FMC Corporation, MSDS sheet dated: 06/26/2009
- De Vooght, V.; Jesus Cruz, M.; Haenen, S.; Wijnhoven, K.; Munoz, X.; Cruz, M.; Munoz, X.; Morell, F.; Nemery, B (2010). "Ammonium persulfate can initiate an asthmatic response in mice". Thorax. 65: 252–257.
{{cite journal}}
: CS1 maint: multiple names: authors list (link) - Pignatti, P.; Frossi, B.; Pala, G.; Negri, S.; Oman, H.; Perfetti, L.; Pucillo, C.; Imbriani, M.; Moscato, G. (2013). "Oxidative activity of ammonium persulfate salt on mast cells and basophils: implication in hairdressers' asthma". Int. Arch. Allergy Immunol. 160: 409–419.
{{cite journal}}
: CS1 maint: multiple names: authors list (link)
For a review of its uses in organic chemistry see Encyclopedia of Reagents for Organic Synthesis, vol. 1, pp. 193–197(1995).
External links
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