Carbonyl nickel powder

Fig. 4. Micro structure of carbonyl nickel powder at various magnifications (a) and (c) lOOOx, (b) and (d) 1500x.

Nickel was first isolated in 1751, and a relatively pure metal was prepared in 1804. In nature, nickel is found primarily as oxide and sulfide ores (USPHS 1977). It has high electrical and thermal conductivities and is resistant to corrosion at environmental temperatures between -20°C and +30°C (Chau and Kulikovsky-Cordeiro 1995). Nickel, also known as carbonyl nickel powder or C.I. No. 77775, has a CAS number of 7440-02-0. Metallic nickel is a hard, lustrous, silvery white metal with a specific gravity of 8.9, a melting point of about 1455°C, and a boiling point at about 2732°C. It is insoluble in water and ammonium hydroxide, soluble in dilute nitric acid or aqua regia, and slightly soluble in hydrochloric and sulfuric acid. Nickel has an atomic weight of 58.71. Nickel is... 

Alcan 756 C.l. 77775 Carbonyl nickel powder CCRIS 427 EINECS 231-111-4 EL12 Fibrex Fibrex P HSDB 1096 Ni 0901-S Ni 270 Ni 4303T Nichel Nickel 200 Nickel 201 Nickel 205 Nickel 207 Nickel 270 Nickel catalyst Nickel compounds Nickel, elemental Nickel, elemental/metal Nickel particles Nickel sponge NP 2 Raney alloy Raney nickel RCH 55/5. Metallic element, used in electroplating, as a hydrogenation catalyst and in iron- and copper-based alloys. Metal mp = 1453° bp (calc) = 2732° d= 8.908. Atomergic Chemetals Inco, Europe Lancaster Synthesis Co. Sigma-Aldrich Fine Chem. 

SYNONYMS alcino, nickel 200, nickel 201, nickel 205, nickel 270 nickel sponge carbonyl nickel powder Raney nickel... 

The sintered-type electrode was developed in Germany in 1932. This electrode is characterized by filling up active materials by an impregnation method into a porous sintered plaque in which carbonyl nickel powder having an average particle diameter of several microns is sintered. 

The production method of the porous sintered plaque includes a dry method and a wet method. With respect to the dry method, carbonyl nickel powder is spread to a Ni wire grid with a sieve or the like, adjusted to a predetermined thickness, and then sintered at 800-1,000° [Celsius] in a reducible gas atmospheres, such as hydrogen gas or butane reformed gas. With respect to the wet method, carbonyl nickel powder, a binder such as CMC or MC, and water are mixed to prepare a slurry. The slurry is applied to a nickel-plated iron thin sheet (perforated sheet) which has an open area ratio of about 50 %, and the thickness is adjusted in a scratching pcrtimi. Then, after drying with a drying furnace, it is sintered at a temperature of 800-1,000° [Celsius] in a reducible gas atmosphere. The typical porosity of the porous sintered plaque is 80-87 %. 

Plaque. The sintered structure before impregnation is generally referred to as plaque. It usually has a porosity of 80 to 85% and ranges in thickness from 0.40 to 1.0 mm. Two generic sintering processes are used (1) the slurry coating process and (2) the dry-powder process. Both processes employ special low-density battery grades of carbonyl nickel powder. 

In the carbonyl process, the Hquid is purified, vaporized, and rapidly heated to ca 300°C which results in the decomposition of the vapor to carbon monoxide and a fine high purity nickel powder of particle sizes <10 fim. This product is useflil for powder metallurgical appHcations (see Metallurgy, powder). Nickel carbonyl can also be decomposed in the presence of nickel powder, upon which the nickel is deposited. This process yields nickel pellets, typically about 0.8 cm dia and of >99.9 wt% purity. 

Nickel [7440-02-0] Ni, recognized as an element as early as 1754 (1), was not isolated until 1820 (2). It was mined from arsenic sulfide mineral deposits (3) and first used in an alloy called German Silver (4). Soon after, nickel was used as an anode in solutions of nickel sulfate [7786-81 A] NiSO, and nickel chloride [7718-54-9] NiCl, to electroplate jewelry. Nickel carbonyl [13463-39-3] Ni(C02)4, was discovered in 1890 (see Carbonyls). This material, distilled as a hquid, decomposes into carbon monoxide and pure nickel powder, a method used in nickel refining (5) (see Nickel and nickel alloys). 

To protect humans and other mammals, proposed air-quality criteria range from 0.01 to less than 1.0 mg/m3 for metallic nickel and slightly soluble nickel compounds, 0.015-0.5 mg/m3 for water soluble nickel compounds, and 0.005 to 0.7 mg/m3 for nickel carbonyl (Table 6.10). Inhalation of nickel subsulfide concentrations (0.11 to 1.8 mg Ni/m3) near the current threshold limit value of 1 mg Ni/m3 can produce detrimental changes in the respiratory tract of rats after only a few days of exposure (Benson et al. 1995). Additional animal studies are recommended to identify minimally effective inhalation exposure levels for the various nickel compounds (USPHS 1993). Continued monitoring of nickel refining, nickel-cadmium battery manufacture, and nickel powder metallurgy installations is recommended because ambient air levels of bioavailable nickel at these... 

Z.S. Wronski, G.J.C. Carpenter, Carbon nanoshells obtained from leaching carbonyl nickel metal powders, Carbon 44(2006) 1779-1789. 

Cold rolling of the powdered precursor NiAlj (10 to 20 fxm particle size), mixed with granules of Mond nickel (carbonyl nickel, which is very ductile) on stainless-steel or nickel foils, creates coatings of 20 to 30% coarse porosity (dp > 10 gm), which firmly adhere to the supporting foil (76). Due to the excessive sheer and stress exerted during rolling, the foils are deformed and must be shaped according to demands after this process has been finished. 

Six grams of 42% nickel, 58 % aluminum catalyst powder, all of which would pass a 150 mesh screen, was mechanically mixed in o porcelain mortar with ten grams of the elemental nickel powder for fifteen minutes. The calculated nickel content of the nickel aluminum powder was 2.52 grams, so that the added nickel was practically four times the nickel contained in the nickel aluminum alloy. The added nickel was not combined chemically with the aluminum, but was thoroughly mixed mechanically with the nickel aluminum powder. The six grams of 42% nickel, 58% aluminum powder had a calculated content of 3.48 grams of aluminum. Seven grams of 76% flake sodium hydroxide were used to make a 25% sodium hydroxide water solution. Potassium hydroxide or other caustic alkali solution may be used in place of sodium hydroxide and nickel carbonyl powder may be used in place of elemental nickel powder. Also, a nickel silicon alloy or an alloy of nickel with another alkali soluble metal may be used in place of the nickel aluminum alloy. 

Derivation Bromination of nickel powder or nickel carbonyl. 

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