Active oxygen sodium perborate

Sodium perborate tnhydrate, NaBO 3H2O or Na2B2(02)2(0H)4 4H2O, triclinic, contains 11.8 wt % active oxygen (96). It has been claimed to have better thermal stabiUty than the tetrahydrate but has not been used commercially. The tnhydrate can be made by dehydration of the tetrahydrate or by crystallization from a sodium metaborate and hydrogen peroxide solution in the present of tnhydrate seeds. Between 18 and 50°C the tnhydrate is more stable but slower to crystallize than the tetrahydrate. Below 15°C the tnhydrate is spontaneously converted into the tetrahydrate. 

Sodium perborate monohydrate, NaBO H2O or Na2B2(02)2(0H)4, 16.0 wt % active oxygen, is commercially prepared by dehydration of the tetrahydrate. The monohydrate has the same peroxyborate anion (7), as the higher hydrates and is the anhydrous sodium salt of this anion. Further dehydration results in decomposition of the peroxyborate. 

Sodium Carbonate Peroxyhydrate. Sodium carbonate peroxyhydrate [15630-89-4], which contains about 14 wt % of active oxygen, has the composition 2Na C(% 3H202. A white, free-flowing solid, it generally can be used in all applications where perborate is used. Despite the fact that sodium carbonate peroxyhydrate has a greater rate of dissolution than sodium perborate tetrahydrate, the latter is usually favored for its good storage stability and better compatibility with the various materials used in formulations (79). 

Perborate is packed in galvanized steel, or wooden, paper lined drums. The commercial product has 97 to 98% NaB02. HgOg. 3 H20, the remainder is sodium tetraborate and carbonate the content of active oxygen varies between 10.1 and 10.2 per cent. 

In solution, sodium perborate monohydrate is similar in action to that of hydrogen peroxide. At elevated temperatures, active oxygen is released and has a bleaching effect but does not affect animal, vegetable, and synthetic fibers [3, 4]. 

The end product contains ca. 10.1 to 10.4% active oxygen (theoretically 10.38%). The bulk density of the perborate is adjusted to that of the other components in detergents ( light perborate ) by special steps in the process. Older manufacturing processes, which started from sodium peroxide or use electrochemical processes, are no longer used. 

Lactic acid, alkyl fatty acids (salicylic acid, glycolic add, benzoic add Chlorhexidine gluconate/acetate Fatty alkyl 1,3-diaminopropane A-Fatty alkyl 3-aminopropionate, A-hydroxyethyl-A-carboxymethyl fatty acid sodium salt of amidoethylamine Ethyl alcohol, propyl alcohol, benzyl alcohol, pine oil Sodium hypochlorite (liquid chlorine bleach), chlorine dioxide, hypochlorous acid, trichloro- and dichloroisocyanuric acids and their salts, sodium perborate and activator, peroxy acid (per acid), magnesium salt of peroxy phthalic acid, oxygen bleach generated from ozone... 

Sodium percarbonate (PCS, NazCOa 1.5 H2O2) is not a true persalt but a simple addition compoimd and, consequently, is less storage stable, as is, than perborate (PBSl or PBS4). It has an active oxygen content of 15% (approximately equal to that of PBSl). Its solubility at 20°C is 120 g/L (i.e., about five times more soluble than PBS4). Its rate of dissolution, in the uncoated form, is about the same as that of PBSl, and its bulk density is somewhat higher (0.9-1.2 kg/L, depending on the method of manufacture). The carbonate liberated contributes to the alkalinity of the wash bath. 

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