Refining of alloys

Boron trichloride is used as a catalyst in polymerization reactions. Other applications include refining of alloys soldering flux and as a component in certain fire extinguishers. It also is used to prepare boron libers and other boron compounds including diborane, sodium borohydride and several adducts. 

Uses Catalyst in organic synthesis source of boron compounds refining of alloys soldering flux electrical resistors extinguishing magnesium fires in heat-treating furnaces mfg. of diborane semiconductor dopant boron vapor deposition raw material (boron fibers)... 

The presence of these acids in crude oils and petroleum cuts causes problems for the refiner because they form stable emulsions with caustic solutions during desalting or in lubricating oil production very corrosive at high temperatures (350-400°C), they attack ordinary carbon steel, which necessitates the use of alloy piping materials. 

It is used in certain nickel-based alloys, such as the "Hastelloys(R)" which are heat-resistant and corrosion-resistant to chemical solutions. Molybdenum oxidizes at elevated temperatures. The metal has found recent application as electrodes for electrically heated glass furnaces and foreheaths. The metal is also used in nuclear energy applications and for missile and aircraft parts. Molybdenum is valuable as a catalyst in the refining of petroleum. It has found applications as a filament material in electronic and electrical applications. Molybdenum is an... 

Cobalt. There is no U.S. mine production of cobalt. Refining of imported nickel—cobalt mattes has not occurred since the mid-1980s. About 1600 t of secondary cobalt was recycled from scrap by 13 faciUties in the United States representing - 22% of total U.S. consumption. The price of the metal was around 44/kg. Most is imported from Zaire and Zambia. Increasing quantities are coming from Russia. Historically, the price of cobalt has been quite volatile and dependent on the pohtical environment in those countries. Cobalt is used in superaHoys, 40% catalysts, 14% paint driers, 11% magnetic alloys, 10% and cemented carbides and other uses, 16%. 

J. Kr. Tuset, Principles of Silicon Eefning International Seminar on Refining and Alloying of Liquid Aluminum and Eerro-AHoys, Trondheim, Norway, Aug. 26,1985. 

Sodium nitrate is also used in formulations of heat-transfer salts for he at-treatment baths for alloys and metals, mbber vulcanization, and petrochemical industries. A mixture of sodium nitrate and potassium nitrate is used to capture solar energy (qv) to transform it into electrical energy. The potential of sodium nitrate in the field of solar salts depends on the commercial development of this process. Other uses of sodium nitrate include water (qv) treatment, ice melting, adhesives (qv), cleaning compounds, pyrotechnics, curing bacons and meats (see Food additives), organics nitration, certain types of pharmaceutical production, refining of some alloys, recovery of lead, and production of uranium. 

Refining. The alloy of bismuth and lead from the separation procedures is treated with molten caustic soda to remove traces of such acidic elements as arsenic and teUutium (4). It is then subjected to the Parkes desilverization process to remove the silver and gold present. This process is also used to remove these elements from lead. 

An obvious refinement of the simple theory for cobalt and nickel and their alloys can be made which leads to a significant increase in the calculated value of the Curie temperature. The foregoing calculation for nickel, for example, is based upon the assumption that the uncoupled valence electrons spend equal amounts of time on the nickel atoms with / = 1 and the nickel atoms with J = 0. However, the stabilizing interaction of the spins of the valence electrons and the parallel atomic moments would cause an increase in the wave function for the valence electrons in the neighborhood of the atoms with / = 1 and the parallel orientation. This effect also produces a change in the shape of the curve of saturation magnetization as a function of temperature. The details of this refined theory will be published later. 

Seeondary smelting and refining and alloying of nonferrous metals and alloys 3341... 

In the refining of the Group V metals (which are more accurately represented as metal-carbon-oxygen alloys), carbon deoxidation is not the only method by which oxygen is removed, because sacrificial deoxidation also occurs simultaneously. The relative extents to which each of these two deoxidation modes contributes to the overall removal of oxygen can be assessed by calculating the ratio of the vapor pressures of carbon monoxide and the metal monoxide over the M-C-0 alloy. The value of this ratio for vanadium at 2000 K is given by the expression... 

Cadmium, as cadmium oxide, is obtained mainly as a by-product during the processing of zinc-bearing ores and also from the refining of lead and copper from sulfide ores (USPHS 1993). In 1989, the United States produced 1.4 million kg of cadmium (usually 0.6 to 1.8 million kg) and imported an additional 2.7 million kg (usually 1.8 to 3.2 million kg). Cadmium is used mainly for the production of nickel-cadmium batteries (35%), in metal plating (30%), and for the manufacture of pigments (15%), plastics and synthetics (10%), and alloys and miscellaneous uses (10%) (USPHS 1993). 

Du and co-workers [48, 66] studied the effect of carbon on the grain refinement of Mg-3A1 alloy. High grain refining efficiency was obtained when these alloys were refined by carbon. A further increase in efficiency was obtained by the combination of 0.2 wt% C and less than 0.2 wt% of a solute element (Ca, Sr) [48, 66], Addition of a higher Ca amount would increase the brittleness of the alloy [60, 66]. Similar results were demonstrated when 0.2 wt% Sr was added in the alloys instead of Ca [48]. 

Carbon is widely used in the catalytic processes of the chemical industry due to its unique characteristics, such as chemical inertness, high surface area and porosity, good mechanical properties and low cost. It is used for the production of chlorine and aluminum, in metal refining (gold, silver, and grain refinement of Mg-Al alloys) as well as for the electrolytic production of hydrogen peroxide and photoelectrochemical water splitting. 

Uses Plasticizer for cellulose resins moth repellant camphor substitute in cellulose solvent manufacturing of smoke candles and explosives rubber vulcanization accelerator insecticide refining aluminum alloys. 

Uses/Sources. Corrosion-resistant alloys, electroplating, production of catalysts, nickel-cadmium batteries nickel subsulfide (NisS2) is encountered in the smelting and refining of certain nickel ores and may be formed in petroleum refining from the use of nickel catalysts. 

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