Metallic nickel

Ma.nufa.cture. The preferred method for making nickel sulfate is adding nickel powder to hot dilute sulfuric acid. Adding sulfuric acid to nickel powder in hot water enhances the formation of H2S. Hydrogen sulfide always forms as a by-product upon reaction of metallic nickel and sulfuric acid. The hberated hydrogen is absorbed by the metal and then reduces the sulfate anion to H2S. 

Ma.nufa.cture. Nickel carbonyl can be prepared by the direct combination of carbon monoxide and metallic nickel (77). The presence of sulfur, the surface area, and the surface activity of the nickel affect the formation of nickel carbonyl (78). The thermodynamics of formation and reaction are documented (79). Two commercial processes are used for large-scale production (80). An atmospheric method, whereby carbon monoxide is passed over nickel sulfide and freshly reduced nickel metal, is used in the United Kingdom to produce pure nickel carbonyl (81). The second method, used in Canada, involves high pressure CO in the formation of iron and nickel carbonyls the two are separated by distillation (81). Very high pressure CO is required for the formation of cobalt carbonyl and a method has been described where the mixed carbonyls are scmbbed with ammonia or an amine and the cobalt is extracted as the ammine carbonyl (82). A discontinued commercial process in the United States involved the reaction of carbon monoxide with nickel sulfate solution. 

Metallic cobalt, metallic nickel and an alloy powder containing 66-67% nickel, 13-16% chromium and 7% iron... 

The phenol is reduced with hydrogen in presence of finely divided metallic nickel which acts as a catalyst. The apparatus is shown in Fig. 79. 

An alloy of nickel was known in China over 2000 years ago, and Saxon miners were familiar with the reddish-coloured ore, NiAs, which superficially resembles CU2O. These miners attributed their inability to extract copper from this source to the work of the devil and named the ore Kupfemickel (Old Nick s copper). In 1751 A. F. Cronstedt isolated an impure metal from some Swedish ores and, identifying it with the metallic component of Kupfemickel, named the new metal nickel . In 1804 J. B. Richter produced a much purer sample and so was able to determine its physical properties more accurately. 

Dimethyl-l,2,2,3-tetramethyl-A -1,2,5-azasilaboroline with [Fe2(CO)9] gives sandwich 62 and sandwich 63 (82AGE207, 82CB738) with Cp)Co(C2H4)2]. With [Ni(CDT)] or in a vapor phase with metallic nickel, sandwich 64 (M =Ni) is formed. The vapor-phase synthesis with iron gives 64 (M = Fe). In all these sandwiches, 62-64, the j " -coordination of the heterocyclic ligand is realized. 

Unfortunately, investigations with ionic liquids containing high amounts of AlEtCl2 showed several limitations, including the reductive effect of the alkylaluminium affecting the temperature stability of the nickel catalyst. At very high alkylaluminium concentrations, precipitation of black metallic nickel was observed even at room temperature. 

Increase in the concentration of metals (nickel, vanadium, etc.) on the catalyst... 

In addition to nickel alloys, nickel also forms an important alloying element in stainless steels and in cast irons, in both of which it confers additional corrosion resistance and improved mechanical and engineering properties, and in Fe-Ni alloys for obtaining controlled physical and magnetic properties (see Chapter 3). With non-ferrous metals nickel also forms important types of alloys, especially with copper, i.e. cupro-nickels and nickel silvers these are dealt with in Section 4.2. 

As with alloys of other metals, nickel alloys may suffer stress-corrosion cracking in certain corrosive environments, although the number of alloy environment combinations in which nickel alloys have been reported to undergo cracking is relatively small. In addition, intergranular attack due to grain boundary precipitates may be intensified by tensile stress in the metal in certain environments and develop into cracking. Table 4.28 lists the major circumstances in which stress corrosion or stress-assisted corrosion of nickel and its alloys have been recorded in service and also shows the preventive and remedial measures that have been adopted, usually with success, in each case. 

Table 12-11 predicts the cell will operate so as to dissolve metallic zinc and deposit metallic nickel, and its voltage will be +0.51 volt This is exactly what occurs in such a cell. Predicting is fun— let s try it again Another cell we studied is based on reaction (52) ... 

X-ray analysis of the spent catalyst (Table XI) revealed metallic nickel and nickel carbide, Ni3C, in the catalyst near the gas inlet and only metallic nickel near the gas outlet. 

In addition to actual synthesis tests, fresh and used catalysts were investigated extensively in order to determine the effect of steam on catalyst activity and catalyst stability. This was done by measurement of surface areas. Whereas the Brunauer-Emmett-Teller (BET) area (4) is a measure of the total surface area, the volume of chemisorbed hydrogen is a measure only of the exposed metallic nickel area and therefore should be a truer measure of the catalytically active area. The H2 chemisorption measurement data are summarized in Table III. For fresh reduced catalyst, activity was equivalent to 11.2 ml/g. When this reduced catalyst was treated with a mixture of hydrogen and steam, it lost 27% of its activity. This activity loss is definitely caused by steam since a... 

The last vertical column of the eighth group of the Periodic Table of the Elements comprises the three metals nickel, palladium, and platinum, which are the catalysts most often used in various reactions of hydrogen, e.g. hydrogenation, hydrogenolysis, and hydroisomerization. The considerations which are of particular relevance to the catalytic activity of these metals are their surface interactions with hydrogen, the various states of its adatoms, and admolecules, eventually further influenced by the coadsorbed other reactant species. 

This is the Mond reaction, first developed by Ludwig Mond in 1890. It is still used forthe production and purification of metallic nickel. A similar reaction is used for the production of Fe(CO)5 but higher temperature is required. 

Bottom plate (metal Nickel (or copper) block) material Nickel tubing 500 pm 100 mm internal diameter length... 

Separation of two metals from a leach solution - as examples, mention may be made of solutions containing cobalt and copper, and nickel and copper. The former solution is treated by metallic cobalt to precipitate copper, and the latter by metallic nickel to precipitate copper. In both cases, the metal added to cement the copper is recovered afterwards. 

Plant resins, poison ivy, poison oak, poison sumac Metals (nickel or gold in jewelry)... 

The base metal nickel now begins to plate out on an appropriate surface, such as a less noble metal. 

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