Movatterモバイル変換

[0]ホーム
URL:

Jump to content
WikipediaThe Free Encyclopedia
Search

Potassium persulfate

From Wikipedia, the free encyclopedia
Not to be confused withPotassium peroxymonosulfate.
Potassium persulfate
Two potassium cations and one peroxydisulfate anion
Two potassium cations and one peroxydisulfate anion
Ball-and-stick model of the crystal structure
Ball-and-stick model of the crystal structure
Potassium persulfate as a white powder
Potassium persulfate as a white powder
Names
Other names
  • potassium peroxydisulfate
  • Anthion
  • potassium perdisulfate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard100.028.893Edit this at Wikidata
EC Number
  • 231-781-8
E numberE922(glazing agents, ...)
RTECS number
  • SE0400000
UNII
UN number1492
  • InChI=1S/2K.H2O8S2/c;;1-9(2,3)7-8-10(4,5)6/h;;(H,1,2,3)(H,4,5,6)/q2*+1;/p-2 ☒N
    Key: USHAGKDGDHPEEY-UHFFFAOYSA-L ☒N
  • InChI=1/2K.H2O8S2/c;;1-9(2,3)7-8-10(4,5)6/h;;(H,1,2,3)(H,4,5,6)/q2*+1;/p-2
    Key: USHAGKDGDHPEEY-NUQVWONBAA
  • [O-]S(=O)(=O)OOS(=O)(=O)[O-].[K+].[K+]
Properties
K2S2O8
Molar mass270.322 g/mol
Appearancewhite powder
Odorodorless
Density2.477 g/cm3[1]
Melting point< 100 °C (212 °F; 373 K) (decomposes)
1.75 g/100 mL (0 °C)
4.49 g/100 mL (20 °C)
Solubilityinsoluble inalcohol
1.467
Structure
triclinic
Hazards
GHS labelling:
GHS03: OxidizingGHS07: Exclamation markGHS08: Health hazard
Danger
H272,H302,H315,H317,H319,H334,H335,H371
P220,P261,P280,P305+P351+P338,P342+P311
NFPA 704 (fire diamond)
Flash pointNon-flammable
Lethal dose or concentration (LD, LC):
802 mg/kg (oral, rat)[2]
Safety data sheet (SDS)ICSC 1133
Related compounds
Otheranions
Potassium sulfite
Potassium sulfate
Potassium peroxymonosulfate
Othercations
Sodium persulfate
Ammonium persulfate
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)
Chemical compound

Potassium persulfate is theinorganic compound with the formulaK2S2O8. Also known aspotassium peroxydisulfate, it is a white solid that is sparingly soluble in cold water, but dissolves better in warm water. This salt is a powerful oxidant, commonly used to initiatepolymerizations.

Structure

[edit]

The sodium and potassium salts are very similar. In the potassium salt, the O-O distance is 1.495 Å. The individual sulfate groups are tetrahedral, with three short S-O distances near 1.43 and one long S-O bond at 1.65 Å.[3]

Preparation

[edit]

Potassium persulfate can be prepared byelectrolysis of a cold solutionpotassium bisulfate insulfuric acid at a high current density.[1][4]

2 KHSO4 → K2S2O8 + H2

It can also be prepared by adding potassium bisulfate (KHSO4) to a solution of the more soluble saltammonium peroxydisulfate (NH4)2S2O8. Several million kilograms of the ammonium, sodium, and potassium salts of peroxydisulfate are produced annually.

Uses

[edit]

This salt is used toinitiate polymerization of various alkenes leading to commercially important polymers such asstyrene-butadiene rubber andpolytetrafluoroethylene and related materials. In solution, the dianion dissociates to give radicals:[5]

[O3SO-OSO3]2− ⇌ 2 [SO4]•−

It is used inorganic chemistry as anoxidizing agent,[6] for instance in theElbs persulfate oxidation ofphenols and theBoyland–Sims oxidation ofanilines.

As a strong yet stablebleaching agent it also finds use in various hair bleaches and lighteners. Such brief and non-continuous use is normally hazard free, however prolonged contact can cause skin irritation.[7]It has been used as animproving agent for flour with theE number E922, although it is no longer approved for this use within the EU.

Precautions

[edit]

The salt is a strong oxidant and is incompatible with organic compounds. Prolonged skin contact can result in irritation.[7]

References

[edit]
  1. ^abBrauer, Georg (1963).Handbook of Preparative Inorganic Chemistry. Vol. 1 (2nd ed.). New York: Academic Press. p. 392.ISBN 978-0121266011.{{cite book}}:ISBN / Date incompatibility (help)
  2. ^Chambers, Michael."ChemIDplus - 7727-21-1 - USHAGKDGDHPEEY-UHFFFAOYSA-L - Potassium persulfate".chem.nlm.nih.gov.
  3. ^Naumov, D.Yu.; Virovets, A.V.; Podberezskaya, N.V.; Novikov, P.B.; Politov, A.A. (1997). "Redetermination of the Crystal Structure of Potassium Peroxodisulfate (K2S2O8)".Zhurnal Strukturnoi Khimii.38: 922-929.
  4. ^Girolami, G. S.; Rauchfuss, T. B.; Angelici, R. J. (1999).Synthesis and Technique in Inorganic Chemistry. Mill Valley, CA: University Science Books.ISBN 0935702482.
  5. ^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 978-3-527-30673-2.
  6. ^Encyclopedia of Reagents for Organic Synthesis, vol. 1, pp. 193–197(1995)
  7. ^abPang, S; Fiume, MZ (January 2001). "Final Report on the Safety Assessment of Ammonium, Potassium, and Sodium Persulfate".International Journal of Toxicology.20 (3):7–21.doi:10.1080/10915810152630710.PMID 11766134.S2CID 25763799.
H, (pseudo)halogens
chalcogens
pnictogens
B, C group
transition metals
organic
Salts and covalent derivatives of thepersulfate ion
H2SO5
H2S2O8		He
LiBeBC(NH4)2S2O8OFNe
Na2S2O8MgAlSiP(SO5)2−
(S2O8)2−		ClAr
KHSO5
K2S2O8		CaScTiVCrMnFeCoNiCuZnGaGeAsSeBrKr
RbSrYZrNbMoTcRuRhPdC20H20N4AgS2O8CdInSnSbTeIXe
CsBa*LuHfTaWReOsIrPtAuHgTlPbBiPoAtRn
FrRa**LrRfDbSgBhHsMtDsRgCnNhFlMcLvTsOg
 
*LaCePrNdPmSmEuGdTbDyHoErTmYb
**AcThPaUNpPuAmCmBkCfEsFmMdNo
Retrieved from "https://en.wikipedia.org/w/index.php?title=Potassium_persulfate&oldid=1322342775"
Categories:
Hidden categories:
[8]ページ先頭
©2009-2026 Movatter.jp