Sodium percarbonate is a chemical substance with formula Na
2H
3CO
6. It is an adduct of sodium carbonate ("soda ash" or "washing soda") and hydrogen peroxide (that is, a perhydrate) whose formula is more properly written as 2 Na
2CO
3 · 3 H
2O
2. It is a colorless, crystalline, hygroscopic and water-soluble solid. It is sometimes abbreviated as SPC.
The product is used in some eco-friendly bleaches and other cleaning products, and as a laboratory source of anhydrous hydrogen peroxide.
Video Sodium percarbonate
History
Sodium percarbonate was first prepared in 1899 by Russian chemist Sebastian Moiseevich Tanatar (Russian: ????????? ????????? ???????) (7 October 1849, Odessa - 30 November 1917, Odessa).
Maps Sodium percarbonate
Structure
At room temperature, solid sodium percarbonate has the orthorhombic crystal structure, with the Cmca crystallographic space group. The structure changes to Pbca as the crystals are cooled below about -30 °C.
Chemistry
Dissolved in water, sodium percabonate yields a mixture of hydrogen peroxide (which eventually decomposes to water and oxygen), sodium cations Na+
, and carbonate CO2-
3.
- 2 Na
2CO
3 · 3 H
2O
2 -> 4 Na+
+ 2 CO2-
3 + 3 H
2O
2
- 2 H
2O
2 -> 2 H
2O + O
2
Production
Sodium percarbonate is produced industrially by crystallization of a solution of sodium carbonate and hydrogen peroxide, with proper control of the pH and concentrations. This is also a convenient laboratory method.
Alternatively, dry sodium carbonate may be treated directly with concentrated hydrogen peroxide solution.
World production capacity of this compound was estimated at several hundred thousand tonnes for 2004.
Uses
As an oxidizing agent, sodium percarbonate is an ingredient in a number of home and laundry cleaning products, including non-chlorine bleach products such as OxyBoost, OxiClean, Tide laundry detergent, and Vanish.
Many commercial products mix a percentage of sodium percarbonate with sodium carbonate. The average percentage of an "Oxy" product in the supermarket is 65% sodium percarbonate and 35% sodium carbonate. The "ultra boosters" seen on infomercials may contain as much as 80% sodium percarbonate. However, sodium percarbonate is less expensive in its pure form and can be adjusted to any percentage the user desires.
Sodium percarbonate can be used in organic synthesis as a convenient source of anhydrous H2O2, in particular in solvents that cannot dissolve the carbonate but can leach the H2O2 out of it. A method for generating trifluoroperacetic acid in situ for use in Baeyer-Villiger oxidations from sodium percarbonate and trifluoroacetic anhydride has been reported; it provides a convenient and cheap approach to this reagent without the need to obtain highly concentrated hydrogen peroxide.
Commercial products
- OxiClean
- Oxyper
- OxyBoost
References
External links
- Organic Chemistry Portal: Sodium percarbonate
- Record in the Household Products Database of NLM
Source of article : Wikipedia
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