Metal salts Nickel sulfide

Bina Selenides. Most biaary selenides are formed by beating selenium ia the presence of the element, reduction of selenites or selenates with carbon or hydrogen, and double decomposition of heavy-metal salts ia aqueous solution or suspension with a soluble selenide salt, eg, Na2Se or (NH 2S [66455-76-3]. Atmospheric oxygen oxidizes the selenides more rapidly than the corresponding sulfides and more slowly than the teUurides. Selenides of the alkah, alkaline-earth metals, and lanthanum elements are water soluble and readily hydrolyzed. Heavy-metal selenides are iasoluble ia water. Polyselenides form when selenium reacts with alkah metals dissolved ia hquid ammonia. Metal (M) hydrogen selenides of the M HSe type are known. Some heavy-metal selenides show important and useful electric, photoelectric, photo-optical, and semiconductor properties. Ferroselenium and nickel selenide are made by sintering a mixture of selenium and metal powder. 

In the second method, a metal salt solution (silver, lead, or bismuth less often nickel, cobalt, or manganese) is applied colloidal sulfur may also be added. Dyeing is based on (1) The reaction of the metal salts with the added sulfur and the sulfur in the hair keratin, which yields metal sulfides, and (2) The deposition of finely divided metals or metal oxides. With these products progressive coloration also is obtained. 

The zinc salt solutions, which currently mainly come from zinc and copper smelters, contain impurities which have to be completely removed prior to use, because all heavy metals form colored sulfides. For the purification step the solution is oxidized with chlorine (pH 4), which precipitates most of the iron and manganese as the oxide-hydrate and part of the cobalt, nickel and cadmium present as their hydroxides. In the second step, the elements nobler than zinc (Ni, Co, Cd, In, Tl, Pb, Cu, Ag) are precipitated as their metals by adding zinc dust and the metals returned to the copper smelters for noble metal extraction. After purification the solutions are adjusted to a particular zinc content. Mixtures of zinc sulfate and zinc chloride solutions are used for manufacturing lithopone types with more than 30% ZnS. 

SYNONYMS (nickel) elemental nickel, nickel catalyst, nickel metal, raney alloy, raney nickel (nickel carbonate) basic nickel carbonate, carbon acid nickel salt (1 1), nickelous carbonate (nickel sulfide) mononickel monosulfide, nickel (II) sulfide, nickel monosulfide, nickelous sulfide. 

Other catalysts are prepared as nearly pure porous metals (Raney nickel, for example) or as precipitated mixtures of oxides, sulfides, or other salts. These porous materials also have large internal surface areas and much greater catalytic activity than if they were dense solids with reaction limited to the external surface. However, active sites inside the particle are less accessible than those on the outside, and the reaction rate often depends on the rates of diffusion of reactants and products in the pores of the solid. 

Potassium or sodium-potassium alloy mixed with ammonium nitrate and ammonium sulfate results in explosion (NFPA 1986). Violent reactions may occur when a metal such as aluminum, magnesium, copper, cadmium, zinc, cobalt, nickel, lead, chromium, bismuth, or antimony in powdered form is mixed with fused ammonium nitrate. An explosion may occur when the mixture above is subjected to shock. A mixture with white phosphorus or sulfur explodes by percussion or shock. It explodes when heated with carbon. Mixture with concentrated acetic acid ignites on warming. Many metal salts, especially the chromates, dichromates, and chlorides, can lower the decomposition temperature of ammonium nitrate. For example, presence of 0.1% CaCb, NH4CI, AICI3, or FeCb can cause explosive decomposition at 175°C (347°F). Also, the presence of acid can further catalyze the decomposition of ammonium nitrate in presence of metal sulfides. 

Cadmium is a bivalent metal that is used as an anticorrosive and, in association with nickel, copper and silver, in the production of conducting alloys. One of its salts (cadmium sulfide) is used as a colorant for paints and rubber cadmium acetate is used in the production of craftware. There are reports in the literature of cadmium granulomas with a sarcoid-like appearance. Occupational exposure to rare metals has been well reviewed recently (McFadden et al. 1989 Kusaka 1993). The histopathological diagnosis is... 

Nickel is present in the earth s crust, occurs naturally in drinking water and in food, and is possibly an essential nutrient for humans. Nickel-related health problems are, however, not caused primarily by nickel in the environment but are related to industrial activity. Nickel is a transitional metal with the atomic number 28. Ni(o) in metal nickel and its alloys, and Ni(II) in nickel salts and stable inorganic compounds are the most prevalent oxidation states. Numerous nickel salts and sulfides with different properties and uses are known. For example, nickel ions are formed when metallic nickel is in contact with sweat. 

Gum etherates are usually used as the depressant of talcum, mica, serpentine, and chlorite. Meantime, they are also applied in the flotation of nickel sulfide ore and nonferrous metals sulfide ores, as well as some nonsulfide minerals such as sylvite and boron salt. According to the foreign patent, the flotation index is still good when gum is used with wetting agent in the flotation of nickel sulfide ore containing 50 % talcum. 

Ruthenium is produced mainly from an anode slime yielded when crude copper or crude nickel, obtained from nickel sulfide ores, is electrolytically refined. The anode slime contains precious metal elements. It is treated with hot aqua regia and platinum, palladium and gold are separated as their chloro complexes. Then, by nitric acid treatment, fusion treatment with NaHS04, and fusion treatment with Na202, silver, rhodium and iridium are separated. The residual ruthenium and osmium salts are dissolved in water, and the osmium is separated by treatment with chlorine, hydrochloric acid and nitric acid. The ruthenium salt is treated with ammonium chloride to afford a ruthenium salt ((NH4)3RuCl6), and the reduction with hydrogen yields ruthenium powder [1,4-6]. 

In this connection, note should be taken of the somewhat remarkable phenomenon that when chemical reactions are conducted on cellophane impregnated with the reagent or the solution of the metal salt, the product of the reaction frequently remains in the substrate in the coUoidal condition. For instance, when metallic sulfide or nickel dimethylglyozime is formed, the cellophane films are stained brown-black or red, although no solid particles are visible with the naked eye. ... 

The salts, oxides, sulfides, etc. come together, so long as the metal has the same electrovalency, for ex., the ferrous compounds are classified with nickel, cobalt, manganese ones, but the ferric compounds, with aluminum and chromic salts. 

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