Peroxoborate

The commercial product is a white, crystalline powder having an active oxygen content of at least 10%. It melts at about 60°C however, if water vapor is free to escape during heating, the crystals do not melt but are converted to the anhydrous peroxoborate. 

In aqueous solution, all the sodium peroxoborates dissociate for the most part into boric acid, or its anion, and hydrogen peroxide. Peroxoborate species are also present in these solutions, depending on the pH and the concentration for the species type. The nature of these species has been extensively examined by classical physicochemical methods (13), by nmr, and by Raman spectroscopy (14—17). Both monomeric and polymeric species are usually present. There is some evidence (18) suggesting that these peroxoborates are more reactive than hydrogen peroxide alone under similar conditions. 

Sodium peroxoborate hexahydrate is an important ingredient of many household detergents, working best at temperatures above 60°C. It is also used in dishwasher detergents, denture cleaners, as well as foot and bath salts. The textile industry generally uses hydrogen peroxide for bleaching, but there are a few areas in which sodium peroxoborate hexahydrate is preferred. 

The toxicity of sodium peroxoborate hexahydrate in solution is equivalent to those of sodium borate and hydrogen peroxide. The LD q (mouse, oral) is 1060 mg/kg (2). Local use of high concentrations in the mouth can cause chemical bums and other problems (25). No TLV has been estabhshed. 

Sodium Peroxoborate Tetrahydrate. The compound sodium peroxoborate tetrahydrate [28962-65-4] (sodium perborate trihydrate), Na2B2(02)2[(0H)J 4H20, was formerly written as NaBO 3H20. A number of procedures have been pubHshed (13) for producing this hydrate most... 

Sodium peroxoborate tetrahydrate is the most stable of the three peroxoborate hydrates under ambient conditions. It has, however, never been commercialised because it is slow when dissolving in water. 

Sodium Peroxoborate. Sodium peroxoborate [10332-33-9] (sodium perborate monohydrate), Na2[82(02)2(011)4], formerly written as NaBO H20, is known only as a microcrystalline powder, made by dehydrating the hexahydrate. The crystal stmcture has not been deterrnined, but the vibrational spectmm (27) indicates the presence of the same cycHc peroxodiborate anion (4) as that in the hexahydrate as well as in the tetrahydrate. 

The product is considered nonha2ardous for international transport purposes. However, it is an oxidising agent sensitive to decomposition by water, direct sources of heat, catalysts, etc. Decomposition of sodium peroxoborate is accompanied by the Hberation of oxygen and heat which can support combustion and cause pressure bursts in confined spaces. Decomposition in the presence of organic material is rapid and highly exothermic. 

The world market in 1993 was about 450,000 t. Sodium peroxoborate is made commercially by Atochem, Ausimont, Caffaro, Degussa, Eka Nobel, Foret, L Air Liquide, Solvay Interox (Belgium, Italy, Germany, United Kingdom, United States), and Treibacher Chemische Werke. The U.S. price in 1994 was in the range 1.32—1.43/kg, the German price was DM 1.35—1.60/kg ( 0.78—0.92/kg). 

The compound was first made commercially in England during World War II as a substitute for sodium peroxoborate, which could no longer be made because of a shortage of borax. It offers some advantages over the peroxoborate and has grown to be an important industrial chemical. 

Sodium pyrophosphate peroxohydrate, Na4P202 2H2O2, was made commercially by PMC in the 1960s but was discontinued. It is less stable than sodium peroxoborate and sodium carbonate peroxohydrate in the soHd state, but more stable than these in solution. Many other phosphate peroxohydrates of the Group 1 and Group 2 metals are known but have found no uses. 

In 1993, the world capacity for sodium peroxoborate hexahydrate (tetrahydrate) was about 900,000 metric tons, of which about one-third was converted to the dehydrated compound (monohydrate). At the then prevailing prices, the total value of this business was about 6 x 10 . The world capacity for sodium carbonate peroxohydrate (percarbonate) was about 60,000 metric tons, valued at about 70 x 10 . ... 

Boron also has a high affinity for oxygen-forming borates, polyborates, borosiUcates, peroxoborates, etc. Boron reacts with water at temperatures above 100°C to form boric acid and other boron compounds (qv). 

Sodium hexakis(formato)molybdate, 3, 1235 Sodium hypochlorite alkene epoxidation manganese catalysts, 6,378 Sodium ions biology, 6, 559 selective binding biology, 6, 551 Sodium molybdate, 3, 1230 Sodium peroxoborate, 3,101 Sodium/potassium ATPase, 6, 555 vanadate inhibition, 3, 567 Sodium pump, 6, 555 mechanism, 6, 556 Sodium pyroantimonate, 3, 265 Sodium salts... 

See entry crystalline hydrogen peroxidates See Sodium peroxoborate (next below)... 

The true peroxoborate has been reported to detonate on light friction [ 1 ]. The common tetrahydrate is not a peroxoborate, but NaBO2.H2O2.3H2O, and while subject to catalytic decomposition by heavy metals and their salts, or easily oxidisable foreign matter, it is relatively stable under mild grinding with other substances [2],... 

Peroxide titanate complexes, 25 98 Peroxide value, 20 827 in soap making, 22 736 Peroxidic compounds, 25 42 Peroxoborates, names, CAS numbers, and IUPAC names of, 18 398t Peroxocarbonates, 28 401 Peroxo compounds, 28 392-393, 397 Peroxodisulfate ion, 28 408 Peroxodisulfates, 28 392, 408-410 Peroxodisulfate salts, 28 418 uses for, 28 408-409 Peroxodisulfuric acid, 28 407 408 Peroxohydrate(s), 24 40 28 411—415 of melamine, 28 415 stabilization of, 28 413 Peroxo molybdate complexes, 2 7 22 Peroxomonophosphate ion, 28 403 Peroxomonophosphoric acid, 28 403 Peroxomonosulfates, 28 406 407... 

Oxygen (Gas), Carbon disulfide, Mercury, Anthracene, 4831 Oxygen (Liquid), Carbon, Iron(II) oxide, 4832 Oxygen difluoride, Hexafluoropropene, Oxygen, 4317 Potassium chlorate, Manganese dioxide, 4017 f Propionyl chloride, Diisopropyl ether, 1163 f Propylene oxide, Sodium hydroxide, 1225 Silver azide, 0023 Silver nitride, 0038 Sodium carbonate, 0552 Sodium peroxoborate, 0155 Tetrafluoroammonium tetrafluoroborate, 0133 Triallyl phosphate, 3184... 

Ammonium hydroxyoxodiperoxochromate(l—), 4230 Ammonium pentaperoxodichromate(2—), 4247 Ammonium peroxoborate, 0146 Ammonium peroxodisulfate, 4576 Ammonium tetraperoxochromate(l—)... 

The reaction of borate salts with hydrogen peroxide in alkaline aqueous solution results in formation of peroxoborates. This reaction is rapid and occurs by nucleophilic attack of the perhydroxyl anion on boric acid,... 

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