Nickel sulfate, decomposition

KAR/MAL] Karwan, T., Malinowski, C., Ptak, W., Sukiennik, M., Equilibrium parameters of nickel sulfate decomposition and its rate, Thermochim. Acta, 23, (1978), 269-282. Cited on page 194. 

Because of the delay in decomposition of the peroxide, oxygen evolution follows carbon dioxide sorption. A catalyst is required to obtain total decomposition of the peroxides 2 wt % nickel sulfate often is used. The temperature of the bed is the controlling variable 204°C is required to produce the best decomposition rates (18). The reaction mechanism for sodium peroxide is the same as for lithium peroxide, ie, both carbon dioxide and moisture are required to generate oxygen. Sodium peroxide has been used extensively in breathing apparatus. 

Thus an active nickel catalyst may be prepared simply by heating the formate in oil at around 240°C for about 1 h this method has been employed in the oil-hardening industry for the preparation of a wet-reduced catalyst,42 although the decomposition temperature is too high for normal oil-hardening and the catalyst may not be prepared directly in a hydrogenation tank, particularly for edible purposes. Nickel formate is prepared by the reaction between nickel sulfate and sodium formate,43 or the direct reaction of basic nickel carbonate44 or nickel hydroxide with formic acid.31... 

SAFETY PROFILE Confirmed human carcinogen. Poison by ingestion, intravenous, and subcutaneous routes. Experimental reproductive effects. Human mutation data reported. When heated to decomposition it emits toxic fumes of SOx. See also NICKEL SULFATE. 

NICKEL SULFATE (7786-81-4, anhydrous 10101-97-0, hexahydrate 10101-98-1, heptahydrate) NiS04 6H20 NiS04 7H20 Noncombustible solid. The aqueous solution is a weak acid. Violent reaction with red phosphorus. Sulfates react violently with aluminum, magnesium. Incompatible with strong acids. Thermal decomposition releases toxic oxides of sulfur and nitrogen. 

EXPLOSION and FIRE CONCERNS (nickel chloride) not flammable mixture of potassium and nickel chloride produces a strong explosion on impact decomposition emits very toxic fumes of Cf (nickel sulfate) not flammable decomposition emits very toxic fumes of ox-... 

A typical electroless plating solution is composed of a cation provider such as nickel sulfate, a reducing agent such as ammonium hypophosphite, and additional additives tiiat help prevent the bath from decomposition, i.e., plating spontaneously. When an activated substrate is immersed in the plating bath at a temperature of 80 C and a pH around 6, nickel cation in the bath are reduced by hypophosphorous acid, and the nucleation of nickel deposition starts at the activated locations. Because nickel readily plates to itself (self-catalysis), the deposition continues and eventually fills the via locations in the dielectric with nickel metal. The reduction reaction can be expressed by the following equations ... 

Spherical clusters of NiO nanoshafts were prepared by chemical precipitation of nickel sulfate followed by thermal decomposition at 280°C in air. The as-prepared NiO nanoshafts present a high specific surface area (113 m /g), they deliver a reversible capacity of approximately 900 mAh/g in the first cycle, but the cycling performance is quite poor. ... 

The filtrate is sulfate-free but all attempts to isolate any solid product result in decomposition to nickel sulfide. 

The advantages of using chloride electrolytes compared with sulfate electrolytes are higher electrical conductivity, lower electrolyte viscosity, lower overpotential for nickel reduction, and higher solubility and activity of nickel. An important factor is the lower anode potential of chlorine evolution compared with oxygen evolution in sulfate electrolytes using the common lead anodes. Chloride electrolytes require insoluble or dimensionally stable anodes, usually titanium coated with an electroactive noble metal or oxide, and a diaphragm system to collect the CI2 gas from the anode. The chlorine liberated at the anode is recycled for use in the leach circuits. In practice, some decomposition of water... 

The main component in nickel sulfamate baths — sulfamate - can be determined in a single rim, in addition to the decomposition product sulfate and other bath constituents such as chloride and bromide (see Fig. 8-32). To achieve a sufficient separation between the sulfamate ions and chloride, both of which elute near the void volume, two identical anion exchangers were used in series, even though this increases the total analysis time to about 20 minutes. 

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