Sodium Perborate NaBO

Similar migration of the other two R groups and hydrolysis of the B-0 bonds leads to the alcohol and boric acid. Retention of configuration is observed in R. Boranes can also be oxidized to borates in good yields with oxygen," with sodium perborate NaBOs," " and with trimethylamine oxide, either anhydrous" or in the form of the dibydrate." The reaction with oxygen is free radical in nature." ... 

Either sodium permanganate or potassium iodide can be used to titrate the sodium perborate (NaBO -dH O). Dissolve 0.2 g of sample in 200 ml distilled water, add 40 ml 6 N H SO, titrate with 0.1 N sodium permanganate until a pink colour appears. The assay of sodium perborate can be calculated using Equations [4.21] and [4.22] ... 

Sodium perborate NaBOs is sometimes added as a solid bleach to help remove stains. It works by generating hydrogen peroxide in water. It s much more gentle on textiles than chlorine bleach. However, it s most effective in hot water, which can present a problem for those of us who like to wash in cold water. 

Bleaches that contain chlorine (hypochlorites) have been used for years, sometimes separately and sometimes incorporated into the detergent. The chlorine acts as an oxidizing agent. Problems with residual chlorine and its odor have led more recently to the use of peroxides, especially sodium perborate (NaBOs). Hydrolysis of the perborate produces hydrogen peroxide (HjOj), which does the bleaching. 

One useful compound that can be obtained by crystallization from a solution of borax and hydrogen peroxide is sodium perborate, NaBOs 4 H2O. This formula is deceptively simple a more precise formula is Na2[B2(02)2(0H)4] 6 H2O. Sodium perborate contains the perborate ion, [B2(02)2(OH)4] ,the structure of which is shown in Figure 21-20. Sodium perborate is a bleach alternative used in many color-safe bleaches. The key to the bleaching action is the presence of the two peroxo groups (—O—O—) bridging the boron atoms in the [B2(02)2(0H)4] ion. 

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. 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. 

Anhydrous Sodium Perborate. Anhydrous sodium perborate [7632-04-4] NaBO, is an ill-defined, powdery material, made by heating... 

Sodium Perborate Hydrates. Peroxyborates are commonly known as perborates, written as if the perborate anion were BO . X-ray crystal stmcture has shown that they contain the dimeric anion [(H0)2B(02)2B(0H)2] (7) (92). Three sodium perborate hydrates, NaBO XH2O (x = 1, 3, and 4), are known. Only the mono- and tetrahydrate are of commercial importance, primarily as bleaching agents (qv) in laundry products. 

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. 

NaBOs. 4 H2O SODIUM PERBORATE tetrahydrate Molecular weight 153.87 ... 

Sodium perborate is available as the so-called tetrahydrate (NaB03 4H20 or PBS4) or monohydrate (NaBOs H2O or PBSl). The monohydrate is produced by dehydration of the tetrahydrate. The perborates are true persalts, having the structure shown in Fig. 1 [7]. It can be seen from the structure that the monohydrate is actually an anhydrous salt and the tetrahydrate is a hexahydrate. The nomenclature of PBSl and PBS4 arose before the true structures of these salts were known. 

Sodium perborate tetrahydrate NaBOs 4H2O 7632-04-4 163.861 wh cry 60 dec reac HjO... 

B 13.22%, Na 28.10%, O 58.68%. NaBO,. Contains, when reasonably fresh, about 95% of the perborate corresp to 9.9% available oxygen. Prepn from sodium metaborate and hydrogen peroxide Leblon, Lambert, U.S. pat. 3,109,706... 

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