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Nickel carbonate, commercial

Ma.nufa.cture. Several nickel oxides are manufactured commercially. A sintered form of green nickel oxide is made by smelting a purified nickel matte at 1000°C (30) a powder form is made by the desulfurization of nickel matte. Black nickel oxide is made by the calcination of nickel carbonate at 600°C (31). The carbonate results from an extraction process whereby pure nickel metal powder is oxidized with air in the presence of ammonia (qv) and carbon dioxide (qv) to hexaamminenickel(TT) carbonate [67806-76-2], [Ni(NH3)3]C03 (32). Nickel oxides also ate made by the calcination of nickel carbonate or nickel nitrate that were made from a pure form of nickel. A high purity, green nickel oxide is made by firing a mixture of nickel powder and water in air (25). [Pg.9]

Nickel Carbonate. Nickel carbonate [3333-67-3], NiCO, is a light-green, rhombic crystalline salt, density 2.6 g/cm, that is very slightly soluble in water. The addition of sodium carbonate to a solution of a nickel salt precipitates an impure basic nickel carbonate. The commercial material is the basic salt 2NiCo2 3Ni(OH)2 4H20 [29863-10-3]. Nickel carbonate is prepared best by the oxidation of nickel powder in ammonia and CO2. Boiling away the ammonia causes precipitation of pure nickel carbonate (32). [Pg.10]

Nickel Fluoroborate. Fluoroboric acid and nickel carbonate form nickel fluoroborate [14708-14-6] Ni(BF 2 6H20. Upon crystallization, the high purity product is obtained (47). Nickel fluoroborate is used as the electrolyte ia specialty high speed nickel plating. It is available commercially as a concentrated solution. [Pg.11]

Two basic carbonates are known. They are 2NiCOs 3Ni(OH)2 4H2O [29863-10-3], and NiCOs 2Ni(OH)2 [12607-70-4], MW 304.17. The second form occurs in nature as a tetrahydrate, mineral, zaratite. Commercial nickel carbonate is usually the basic salt, 2NiCOs 3Ni(OH)2 dHsO. [Pg.611]

Some preliminary runs using nickel carbonate in the presence of hydrogen have also yielded promising results. In these runs the nickel carbonate was reduced in situ to finely divided nickel which presumably functioned as the catalyst. Commercially available nickel powders did not appear to be as effective as Raney nickel or nickel produced in situ. [Pg.355]

Acetylene-Based Routes. Walter Reppe, the father of modem acetylene chemistry, discovered the reaction of nickel carbonyl with acetylene and water or alcohols to give acryUc acid or esters (75,76). This discovery led to several processes which have been in commercial use. The original Reppe reaction requires a stoichiometric ratio of nickel carbonyl to acetylene. The Rohm and Haas modified or semicatalytic process provides 60—80% of the carbon monoxide from a separate carbon monoxide feed and the remainder from nickel carbonyl (77—78). The reactions for the synthesis of ethyl acrylate are... [Pg.155]

Fluorocarbons are made commercially also by the electrolysis of hydrocarbons in anhydrous hydrogen fluoride (Simons process) (14). Nickel anodes and nickel or steel cathodes are used. Special porous anodes improve the yields. This method is limited to starting materials that are appreciably soluble in hydrogen fluoride, and is most useflil for manufacturing perfluoroalkyl carboxyflc and sulfonic acids, and tertiary amines. For volatile materials with tittle solubility in hydrofluoric acid, a complementary method that uses porous carbon anodes and HF 2KF electrolyte (Phillips process) is useflil (14). [Pg.283]

Soft magnetic materials are characterized by high permeabiUty and low coercivity. There are sis principal groups of commercially important soft magnetic materials iron and low carbon steels, iron—siUcon alloys, iron—aluminum and iron—aluminum—silicon alloys, nickel—iron alloys, iron-cobalt alloys, and ferrites. In addition, iron-boron-based amorphous soft magnetic alloys are commercially available. Some have properties similar to the best grades of the permalloys whereas others exhibit core losses substantially below those of the oriented siUcon steels. Table 1 summarizes the properties of some of these materials. [Pg.368]

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. [Pg.12]

Butene. Commercial production of 1-butene, as well as the manufacture of other linear a-olefins with even carbon atom numbers, is based on the ethylene oligomerization reaction. The reaction can be catalyzed by triethyl aluminum at 180—280°C and 15—30 MPa ( 150 300 atm) pressure (6) or by nickel-based catalysts at 80—120°C and 7—15 MPa pressure (7—9). Another commercially developed method includes ethylene dimerization with the Ziegler dimerization catalysts, (OR) —AIR, where R represents small alkyl groups (10). In addition, several processes are used to manufacture 1-butene from mixed butylene streams in refineries (11) (see BuTYLENEs). [Pg.425]

Easily decomposed, volatile metal carbonyls have been used in metal deposition reactions where heating forms the metal and carbon monoxide. Other products such as metal carbides and carbon may also form, depending on the conditions. The commercially important Mond process depends on the thermal decomposition of Ni(CO)4 to form high purity nickel. In a typical vapor deposition process, a purified inert carrier gas is passed over a metal carbonyl containing the metal to be deposited. The carbonyl is volatilized, with or without heat, and carried over a heated substrate. The carbonyl is decomposed and the metal deposited on the substrate. A number of papers have appeared concerning vapor deposition techniques and uses (170—179). [Pg.70]

The standard quality of commercially pure nickel (nickel 99% minimum, carbon 0.15% maximum nickel 200/201) can be readily welded and fabricated in all wrought forms and as castings. However, it is restricted to... [Pg.74]

A good catalyst is also stable. It must not deactivate at the high temperature levels (1300 to 1400°F) experienced in regenerators. It must also be resistant to contamination. While all catalysts are subject to contamination by certain metals, such as nickel, vanadium, and iron in extremely minute amounts, some are affected much more than others. While metal contaminants deactivate the catalyst slightly, this is not serious. The really important effect of the metals is that they destroy a catalyst s selectivity. The hydrogen and coke yields go up very rapidly, and the gasoline yield goes down. While Zeolite catalysts are not as sensitive to metals as 3A catalysts, they are more sensitive to the carbon level on the catalyst than 3A. Since all commercial catalysts are contaminated to some extent, it has been necessary to set up a measure that will reflect just how badly they are contaminated. [Pg.16]

There are several types of mesh available, and these are identified by mesh thickness, density, wire diameter and weave pattern. Table 4-9 identifies most of the commercial material now available. The knitted pads are available in any material that can be formed into the necessary weaves, this includes stainless steels, monel, nickel, copper, aluminum, carbon steel, tantalum, Hastelloy, Saran, polyethylene, fluoropolymer, and glass multi-filament. [Pg.247]

The discussion so far has been limited to the structure of pure metals, and to the defects which exist in crysteds comprised of atoms of one element only. In fact, of course, pure metals are comparatively rare and all commercial materials contain impurities and, in many cases also, deliberate alloying additions. In the production of commercially pure metals and of alloys, impurities are inevitably introduced into the metal, e.g. manganese, silicon and phosphorus in mild steel, and iron and silicon in aluminium alloys. However, most commercial materials are not even nominally pure metals but are alloys in which deliberate additions of one or more elements have been made, usually to improve some property of the metal examples are the addition of carbon or nickel and chromium to iron to give, respectively, carbon and stainless steels and the addition of copper to aluminium to give a high-strength age-hardenable alloy. [Pg.1270]

This paper surveys the field of methanation from fundamentals through commercial application. Thermodynamic data are used to predict the effects of temperature, pressure, number of equilibrium reaction stages, and feed composition on methane yield. Mechanisms and proposed kinetic equations are reviewed. These equations cannot prove any one mechanism however, they give insight on relative catalyst activity and rate-controlling steps. Derivation of kinetic equations from the temperature profile in an adiabatic flow system is illustrated. Various catalysts and their preparation are discussed. Nickel seems best nickel catalysts apparently have active sites with AF 3 kcal which accounts for observed poisoning by sulfur and steam. Carbon laydown is thermodynamically possible in a methanator, but it can be avoided kinetically by proper catalyst selection. Proposed commercial methanation systems are reviewed. [Pg.10]

Nickel. As a methanation catalyst, nickel is presently preeminent. It is relatively cheap, it is very active, and it is the most selective to methane of all the metals. Its main drawback is that it is easily poisoned by sulfur, a fault common to all the known active methanation catalysts. The nickel content of commercial nickel catalysts is 25-77 wt %. Nickel is dispersed on a high-surface-area, refractory support such as alumina or kieselguhr. Some supports inhibit the formation of carbon by Reaction 4. Chromia-supported nickel has been studied by Czechoslovakian and Russian investigators. [Pg.23]

Figure 134 is a sketch of some of the details around the anode. The carbon piece is 35 cm long and 3.5 cm in diameter. The metal hanger to the carbon connection shown was made with a nickel split sleeve with commercial galvanized steel banding clamps. (Nickel and Monel alloy banding clamps did not work well they stretched.) This mode of connec-... [Pg.534]

At present, most commercial hydrogen is obtained as a by-product of petroleum refining in a sequence of two catalyzed reactions. The first is a re-forming reaction, in which a hydrocarbon and steam are converted into carbon monoxide and hydrogen over a nickel catalyst ... [Pg.706]


See other pages where Nickel carbonate, commercial is mentioned: [Pg.217]    [Pg.502]    [Pg.619]    [Pg.77]    [Pg.1124]    [Pg.95]    [Pg.178]    [Pg.472]    [Pg.500]    [Pg.180]    [Pg.374]    [Pg.388]    [Pg.332]    [Pg.5]    [Pg.15]    [Pg.437]    [Pg.161]    [Pg.218]    [Pg.164]    [Pg.196]    [Pg.295]    [Pg.477]    [Pg.783]    [Pg.409]    [Pg.7]    [Pg.69]    [Pg.360]    [Pg.492]    [Pg.422]   
See also in sourсe #XX -- [ Pg.3 , Pg.611 ]




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