Reduction by oxidation

The formation of a red precipitate of copper(I) oxide by reduction of Cu(II) is taken as a positive test for an aldehyde Carbohydrates that give positive tests with Benedict s reagent are termed reducing sugars... 

Chromium oxide is mixed with aluminum powder, placed in a refractory-lined vessel, and ignited with barium peroxide and magnesium powder. The reaction is exothermic and self-sustaining. Chromium metal of 97—99% purity is obtained, the chief impurities being aluminum, iron, and silicon (Table 4). Commercial chromium metal may also be produced from the oxide by reduction with silicon in an electric-arc furnace. 

Palladium catalysts have been prepared by fusion of palladium chloride in sodium nitrate to give palladium oxide by reduction of palladium salts by alkaline formaldehyde or sodium formate, by hydrazine and by the reduction of palladium salts with hydrogen.The metal has been prepared in the form of palladium black, and in colloidal form in water containing a protective material, as well as upon supports. The supports commonly used are asbestos, barium carbonate, ... 

Carbon monoxide is widely used as a fuel in the form of producer gas or water gas and is also formed during the isolation of many metals from their oxides by reduction with coke. Producer gas is obtained by blowing air through incandescent coke and consists of about 25% CO, 4% CO and 70% N2, together with traces of Hi, CHj and O2. The reactions occurring during production are ... 

Pure elemental silicon is a hard, dark gray solid with a metallic luster and with a crystalline structure the same as that of the diamond form of carbon. For this reason, silicon shows many chemical and physical similarities. There is also a brown, powdery form of silicon having a microcrystalline form. The element is prepared commercially by reducing the oxide by reacting it with carbon (as coke) in electric furnaces. On a small scale, silicon has been obtained from the oxide by reduction with aluminum meted. 

Two contrasting conclusions have been reported in the reactions of lithium aluminium hydride in THF with phosphine oxides and phosphine sulphides respectively. The secondary oxide, phenyl-a-phenylethylphos-phine oxide (42), has been found to be racemized very rapidly by lithium aluminium hydride, and this observation casts some doubt on earlier reports of the preparation of optically active secondary oxides by reduction of menthyl phosphinates with this reagent. A similar study of the treatment of (/ )-(+ )-methyl-n-propylphenylphosphine sulphide (43) with lithium aluminium hydride has revealed no racemization. These results have been rationalized on the basis of the preferred site of attack of hydride on the complexed intermediate (44), which, in the case of phosphine oxides (X = O), is at phosphorus, and in the case of the sulphides (X = S), is at sulphur. Such behaviour is comparable to that observed during the reduction of phosphine oxides and sulphides with hexachlorodisilane. ... 

Roasting arsenic sulfide in air produces the oxide, and the element is obtained from the oxide by reduction with carbon. 

Suter, D., S. Banwart, and W. Stumm (1991), "Dissolution of Hydrous Iron(III) Oxides by Reductive Mechanisms", Langmuir 7, 809-813. 

Thuhum metal is prepared from its oxide by reduction with lanthanum at its melting point of 1,545°C. Thuhum is separated from lanthanum by subh-mation in vacuum. The metal vapor is condensed into crystalline metal in purified form free from lanthanum. 

Refractory metals such as titanium and zirconium can be won from their oxides by reduction with metals which have oxides with a high heat of formation. Of these, only calcium (or calcium hydride) is capable of producing refractory metals in purities approaching those required for metallurgical uses. 

Rhenium (III) chloride, 1 182 Rhenium (V) chloride, 1 180 Rhenium(VI) oxide, by reduction of Re207 with CO, 3 187 by reduction of Re207 with diox-ane, 3 186... 

As was stated previously, metal cannot disperse as a monolayer onto catalyst supports. However, oxide precursors of metals can monolayer disperse on supports, and supported metal particles can be prepared from the monolayer-dispersed oxide by reduction. 

Cobaltous Oxide, Cobalt Monoxide, CoO, may be obtained from cobaltic oxide by reduction in a current of ammonia,1 or of hydrogen at about 350° C. At higher temperatures metallic cobalt is obtained. 

Five analyses of cupric oxide by reduction in hydrogen furnished the ratio... 

The metal is obtained from the oxides by reduction with Al. A large use of Mn is in ferromanganese for steels. 

Tri-3-amino-tri-p-tolylarsine, formed from the nitro-oxide by reduction wth tin and hydrochloric acid, crystallises in prisms, M.pt. 198° C. It yields a hydrochloride, crystallising in fine, colourless needles, and a crystalline acid stdphate. The triacetyl derivative melts at 228° C., and a ibenzyl derivative (CH3.C8H3.NH.CH2.CgH5)3A,s is formed by heating the amino-arsine with benzyl chloride (3 mols.), but has only been isolated in the form of its hydrochloride. The amino-arsine also condenses with benzaldehyde and with diazobenzene cliloride. 

Reduction and Oxidation.—By reduction with zinc, phenols yield hydrocarbons. 

Mercuri"bis-4- nitrophenor is isolated from its sodium salt, the latter being obtained from the corresponding oxide by reduction with sodium sulphide. This oxide is formed from sodium p-nitrophenolate and mercuric acetate, the two being boiled in aqueous solution. 

Pidgeon process. (ferrosilicon process sih-cothermic process). Process for the production of high-purity magnesium metal from dolomite or magnesium oxide by reduction with ferrosilicon at 1150C under high vacuum. 

Germanium is recovered from its oxide by reduction with hydrogen ... 

Platinum oxide Benzimidazole 3-oxides by reductive ring closure... 

Of course, RDP is very suitable to deposit noble metals in view of their facile reduction from aqueous solutions. A number of studies have shown that attractive results can also be obtained with non-noble metals and with metal oxides and metal sulfides. De Jong [9, 42] has studied the deposition of molybdenum (hydr)oxide by reduction of ammonium molybdate with hydrazine according to the reaction... 

Goldschmidt process A process for extracting certain metals from their oxides by reduction with aluminum, named for German chemist Hans Goldschmidt (1861-1923), who discovered it. See thermite. 

For steam activated carbons as well as chemical activated carbons the kind and the number of the functional groups can be changed by oxidation, by reduction with different reactants or by heat treatment in inert atmosphere under various conditions. 

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