What Is Percarbonic Acid?
Percarbonic acid is the general term for peracetic acids of carbonic acid, namely peroxymonocarbonic acid H2CO4 (also known as hydroperoxyformic acid and peroxydicarbonic acid H2C2O6).
Peroxide is narrowly defined as an organic peroxide having the peroxy group -O-O- and the general structural formula R-O-O-R. In particular, compounds with the R-O-O-H structure, in which hydrogen is substituted on oxygen, are called hydroperoxides. Among these, compounds with a structure in which the hydroxy group -OH of oxoacid is replaced by the hydroperoxide group -OH are peracids. Percarbonic acid is one of these peracids.
Percarbonic acid decomposes rapidly in the presence of metal powder and other contaminants and may explode. However, it is relatively stable in the absence of contaminants.
Uses of Percarbonic Acid
Uses of percarbonic acid itself are very limited. However, the salts of percarbonic acid are mainly used for their oxidizing properties.
For example, potassium peroxydicarbonate K2C2O6, like H2O2, exhibits both oxidizing and reducing effects. Therefore, it has been used as a reagent in microscopy, in photography (to remove residual hypo), as an oxidizing agent in chemical analysis, and in textile printing. It is however not widely used today.
Note that “sodium percarbonate,” used as an ingredient in household oxygen bleaches and disinfectants/deodorizers, is a common name and is not the sodium salt of percarbonic acid. This compound is an addition compound of sodium carbonate and hydrogen peroxide in a 2:3 molar ratio and is represented by the chemical formula Na2CO3-1.5H2O2.