Oxidizing agents peroxydisulfates

Other oxidizing agents that can be used include nitric acid, hydrogen peroxide, peroxydisulfate, chlorate and the pervanadyl ion. The anhydrous... 

Oxidation of the complexes [Ag(Py)4][MoF6] and [Ag(Py)2][UF6] in acetonitrile by MoF6 and UF6, respectively, leads to the silver(III) compounds [Ag(Py)4(NCMe)][MoF6]3 and [Ag(Py)2(NC-Me)3][UF6]3, which are strong oxidizing agents.167 Other pyridine silver(III) complexes have been obtained by oxidation of silver nitrate and ammonia with ammonium peroxydisulfate in aqueous... 

A breaker an enzyme (at T<140°F), strong oxidizing agent, or an acid, is used to depolymerize polysaccharides and break crosslinks such that viscosity declines at a controlled rate so that the proppant may be deposited in the fracture. Too rapid proppant dropout would cause a premature "sand-out" which prevents future extension of the fracture. Peroxydisulfates are the most frequently used breakers. Less reactive organic peroxides may be preferred for high temperature formations (85). 

Monofluorinated hydroquinone and quinone are obtained by stepwise oxidation of 2-fluorophenol(l) using different oxidation agents.167 In the first stage, potassium peroxydisulfate is applied and the resulting hydroquinone 2 is further oxidized to 3 by ammonium cerium(IV) nitrate.167... 

Peroxydisulfuric acid, H2S20s, is a colorless solid that has a melting point of 65 °C. The acid and its salts are strong oxidizing agents, and the acid is not very stable. The sodium, potassium, and ammonium salts are most commonly used in oxidation reactions. The peroxydisulfate ion is generated by the anodic oxidation of bisulfate as represented by the equation... 

Related chemistry has been demonstrated for reactions involving initial reduction of one species and concomitant reduction of a second species that leads to production of a strong oxidizing agent. The peroxydisulfate dianion decomposes upon reduction, to produce SO4, which can annihilate with an anion radical to yield a luminescent species. White and Bard demonstrated this for reduction of solutions containing tris(2,2 -bipyridine) ruthenium(Il), [Ru(bpy)3] +, in the presence of S20g as shown below [22] ... 

Ammonium peroxydisulfate, (NH4)2S20h, is also a powerful oxidizing agent. In acidic solution, it converts chromium(lll) to dichromate, cerium(III) to cerium(IV), and manganese(II) to permanganate. The half-reaction is... 

The intercalation of PANI in zirconium phosphate (ZrP) was also reported by Chang et al. [69]. Different phases of zirconium phosphate, such as y-ZrP, the dihydrogen form of a-ZrP [o -ZrP(HH)], and o -ZrP(NaNa), were intercalated with aniline by either ion-exchange or adsorption, and then polymerized by oxidizing agents such as ammonium peroxydisulfate and iron (III) chloride. The resulting polyaniline nanocomposites showed measurable electrical conductivities, as listed in Table 6.3. 

Polyaniline salts may also be deposited by in situ adsorption polymerization" in a few minutes, as strongly adhering films on a variety of substrates/ such as natural and synthetic fibers and textiles,8 plastic, glass, silver chloride pellets etc.,9 by immersing the substrate in a freshly mixed acidic aqueous solution of aniline and oxidizing agent, such as ammonium peroxydisulfate. It is believed that a reactive intermediate, possibly an oligomeric radical cation of aniline, is first adsorbed, which subsequently polymerizes.8... 

In addition, one-phase smfactant-assisted chemical method has been utilized to synthesize PANI nanofiber, which was doped with CSA and 2-acrylamido-2-methyl-l-propanesulfonic acid, in large quantities [291]. A chemical oxidative polymerization of aniline has been carried out using ammonium peroxydisulfate as an oxidizing agent in the presence of nonionic surfactant. A precipitate of doped emeraldine salt is composed of PANI nanofiber, which has the diameter of 30-50 nm and exhibits the conductivity of 1 -5 S cm at RT. Another piece of research has been done through chemical oxidation polymerization of aniline in a surfactant gel, which was formed by a mixture of hexadecyltrimethylammonium chloride, acetic acid, anihne, and water at - 7 °C [292]. The dendritic PANI nanofiber has the diameter of 60-90 nm and the length of 1 -2 jim. Extended works have been performed by the electrospinning method [293]. It should be taken into account that PANI-CSA fiber shape could be influenced by the synthetic variables such as solvent, surface tension, viscosity, and solution conductivity. 

Photooxidation of organic phosphorus may be performed by UV irradiation on the untreated sample, and relying on the dissolved oxygen present in the sample to provide an adequate source of oxygen or hydroxyl radicals. However, it is more common that hydrogen peroxide, peroxydisulfate, ozone, or other oxidizing agents are added to enhance the completeness of the oxidation process. 

Our recent surface analyses of powdered activated carbon [5] has been extended to the more regularly defined surfaces exhibited by ACC. These adsorbents often display a "memory" in that their physical and chemical resistance submits to various solvents, albeit to a lesser extent than their parent (un-carbonised) material. We treated two microporous ACC samples with an excessive aqueous oxidizing agent, 4M NaOH, and milder conditions provided by 10 % (w/vol) aqueous ammonium and potassium peroxydisulfates solutions. The oxidation differently affects the distribution of surface carbon-oxygen structures, leading to different adsorption behaviour of ACC samples. 

Other possible oxidizing agents—for example, peroxydisulfate or ozone—although thermodynamically feasible, are evidently too slow. The reason for the difficulty in preparing perbromic acid is not satisfactorily understood. This is another example of the anomalous properties of elements that follow the completion of the 3d subshell, which we have encountered previously (see Chapter 9, p. 243 and Chapter 14, p. 385). 

TOC can be determined by a technique that uses a dissolved oxidizing agent promoted by ultraviolet hght. Potassium peroxydisulfate, K 28203, can be used as an oxidizing agent to be added to the sample. Phosphoric acid is also added to the sample, whieh is sparged with air or nitrogen to drive off CO2 formed from HCOj ... 

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