Oxidants perborate

Its solutions are naturally alkaline (pH 10-10.5) and these conditions promote oxidation reactions with hydrogen peroxide, especially those involving the nucleophilic attack by the perhydroxyl anion, HOO [24], With the use of an appropriate metal or nonmetal catalyst, free radical oxidation and other redox oxidation pathways are possible with this oxidant. Perborates find application in at least one oilfield chemical activity, namely as a so-called oxidative polymer breakers for spent fracturing fluids (see 17.2.1.2). 

Prepared by use of HjOj or by electrolytic oxidation. Persulphuric acids, perborates, are of importance. (Permanganates, perchlorates and periodates are not salts of per-acids.) Organic per-acids are prepared similarly. The... 

Detecting the presence of small, even invisible, amounts of blood is routine. Physical characteristics of dried stains give minimal information, however, as dried blood can take on many hues. Many of the chemical tests for the presence of blood rely on the catalytic peroxidase activity of heme (56,57). Minute quantities of blood catalyze oxidation reactions between colorless materials, eg, phenolphthalein, luco malachite green, luminol, etc, to colored or luminescent ones. The oxidant is typically hydrogen peroxide or sodium perborate (see Automated instrumentation,hematology). 

Neutralizing Lotion. The principal active ingredient of cold wave neutralizers is usually an oxidizing agent. The most popular is hydrogen peroxide [7722-84-1J, employed at a concentration of 1—2% it continues to find widespread use. Aqueous solutions of sodium bromate [7789-38-0] at a concentration of 10—20% occasionally are used and are technically preferred over the peroxide formulations because of excellent stabiUty and absence of hair bleaching. Neutralizing powders appear to be on the decline but formulations stiU in use consist of sodium perborate [7632-04-4] combined with hexametaphosphates to improve solubiUty in hard water. 

Nitroso compounds are formed selectively via the oxidation of a primary aromatic amine with Caro s acid [7722-86-3] (H2SO ) or Oxone (Du Pont trademark) monopersulfate compound (2KHSO KHSO K SO aniline black [13007-86-8] is obtained if the oxidation is carried out with salts of persulfiiric acid (31). Oxidation of aromatic amines to nitro compounds can be carried out with peroxytrifluoroacetic acid (32). Hydrogen peroxide with acetonitrile converts aniline in a methanol solution to azoxybenzene [495-48-7] (33), perborate in glacial acetic acid yields azobenzene [103-33-3] (34). 

Conversion of the nitrile to the amide has been achieved by both chemical and biological means. Several patents have described the use of modified Raney nickel catalysts ia this appHcation (25,26). Also, alkaH metal perborates have demonstrated their utiHty (27). Typically, the hydrolysis is conducted ia the presence of sodium hydroxide (28—31). Owiag to the fact that the rate of hydrolysis of the nitrile to the amide is fast as compared to the hydrolysis of the amide to the acid, good yields of the amide are obtained. Other catalysts such as magnesium oxide (32), ammonia (28,29,33), and manganese dioxide (34) have also been employed. 

NOTE Most inhibitors are present to the extent of 0.2 to 0.5 %. Where bro-mate or perborate is used as an oxidizing cleaner or copper passivator, it may be necessary to add 1 to 1.5% inhibitor, to ensure that pitting or gouging does not occur. 

Impurities in CL have also been destroyed by oxidation with ozone22 followed by distillation. Ozonation treatment of waste CL leaves no ionic impurities. However, the most commonly used oxidizing agents are potassium permanganate, perboric acid, perborate, and potassium bromate. Treatment of CL with these oxidizing agents is carried out in a neutral medium at 40-60°C. Strongly alkaline or acidic conditions accelerate the oxidation of CL to form isocyanates. Hie undesirable oxidation reaction is fast above pH 7 because of the reaction with isocyanate to form carbamic acid salts, which shifts the equilibrium to form additional isocyanate. 

In a related reaction, primary aromatic amines have been oxidized to azo compounds by a variety of oxidizing agents, among them Mn02, lead tetraacetate, O2 and a base, barium permanganate, and sodium perborate in acetic acid, tert Butyl hydroperoxide has been used to oxidize certain primary amines to azoxy compounds. 

All classes of primary amine (including primary, secondary, and tertiary alkyl as well as aryl) are oxidized to nitro compounds in high yields with dimethyl dioxirane." Other reagents that oxidize various types of primary amines to nitro compounds are dry ozone, various peroxyacids," MeRe03/H202,"" Oxone ," ° tcrt-butyl hydroperoxide in the presence of certain molybdenum and vanadium compounds, and sodium perborate." ... 

Many other peroxy compounds can analogously be produced in the region of HAP for instance, sodium perborate Na2(B03)2 (from sodium metaborate NaB02) and peroxycarbonates. These compounds are used as stable oxidizing and bleaching agents. 

Magnesium diborate Magnesium perborate Boron oxide Titanium diboride Boron carbide... 

The instability of DAST-type brighteners towards chlorine-containing bleaches has been mentioned already. They also show limited stability towards per-acids. As recommended washing temperatures have tended to fall in recent years, a bleach consisting of sodium perborate activated by addition of tetra-acetylethylenediamine (11.63) has become an important component of household detergent formulations. This system is effective at temperatures as low as 40-50 °C. Since the FBA may be sensitive to the activated oxidant, however, in some formulations it is necessary to protect compounds such as 11.60 or 11.61 by encapsulating either the brightener or the activator, if adequate shelf-life is to be maintained. 

Hazards attendant on the use of this powerful oxidant may in many cases be eliminated by substitution with sodium perborate (actually sodium borate hydrogen peroxidate) [1]. One of several wooden boxes of the peroxide (not clearly labelled as such) exploded with great violence dining handling operations. It seems likely that contamination with a combustible material, or possibly with moisture, had occurred [2],... 

Various convenient methods for the oxidation of oximes to nitro compounds have been developed in recent years. Olah has reported a convenient oxidation of oximes to nitro compounds with sodium perborate in glacial acetic acid (Eq. 2.60).122... 

A Simple and Convenient Method for the Oxidation of Organoboranes Using Sodium Perborate Preparation of (+)-Isopinocampheol. 

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