This paper reviews these methods of extracting and separating tin from different kinds of tin-bearing secondary resources. Discover the world's research. Content uploaded by Yuanbo Zhang....
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In 1853 the method known as offset lithography (or offset ) was first patented by John Strather of England. The principle was not practically applied until the 1870s, when rubber offset rollers were used on flat-bed presses for on metals. In 1860 the phototransfer process was patented, enabling a photographic image on ...
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Frank E. Goodwin Adolph L. Ponikvar. Lead processing - Smelting, Alloying, Refining: Refined lead usually has a purity of 99 to 99.99 percent, but lead of 99.999 percent purity (known as "five nines") is becoming more common commercially. At these levels, the grades of lead differ mostly by their bismuth content.
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chromium. chromium processing, preparation of the ore for use in various products. Chromium (Cr) is a brilliant, hard, refractory metal that melts at 1,857 °C (3,375 °F) and boils at 2,672 °C (4,842 °F). In the pure state it is resistant to ordinary corrosion, resulting in its application as an electroplated protective coating for other metals.
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Notable tin compounds include tin (II) chloride used in galvanizing, dyeing, and perfume production; tin (II) fluoride, which provides the fluoride in some …
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The Harris process of softening and dezincing is designed to remove impurities from desilvered lead by stirring a mixture of molten caustic salts at a temperature of 450–500 °C (840–930 °F) into the molten lead. Metallic impurities react with the chemicals and are collected in the form of their oxides or oxysalts.
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Materials processing, operations that transform industrial materials from raw materials into finished parts or products. In the early 19th century the basic machines for forming, shaping, and cutting were developed. Since then, materials-processing methods, techniques, and machinery have grown in variety and number.
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Tin has a low melting point of 232°C, and liquid tin easily alloys with and wets other metals. 1, 2 Metallic tin is chemically stable and nontoxic, so it is widely used …
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copper processing, the extraction of copper from its ores and the preparation of copper metal or chemical compounds for use in various products. samovar. Copper samovar. In its pure form or as an alloy, copper (Cu) is one of the most important metals in society. The pure metal has a face-centred cubic crystal structure, and there is no critical ...
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recycling, recovery and reprocessing of waste materials for use in new products. The basic phases in recycling are the collection of waste materials, their processing or manufacture into new products, and the purchase of those products, which may then themselves be recycled. Typical materials that are recycled include iron and …
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manganese processing, preparation of the ore for use in various products.. Manganese (Mn) is a hard, silvery white metal with a melting point of 1,244 °C (2,271 °F). Ordinarily too brittle to be of structural value itself, it is an essential agent in steelmaking, in which it removes impurities such as sulfur and oxygen and adds important physical properties to …
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Mercury processing - Extraction, Refining, Recovery: The pyrometallurgical extraction of mercury from its ore is essentially a distillation process. When heat is applied to the sulfide ore in the presence of air, oxygen combines with the sulfur to form sulfur dioxide, and the metal is liberated at a temperature above its boiling point. The gases are then passed …
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zinc processing, the extraction of zinc from its ores and the preparation of zinc metal or chemical compounds for use in various products. Zinc (Zn) is a metallic element of hexagonal close-packed (hcp) crystal structure and a density of 7.13 grams per cubic centimetre. It has only moderate hardness and can be made ductile and easily worked at ...
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Aluminum processing - Ores, Refining, Alloying: Aluminum is the third most abundant element on Earth's surface. Only oxygen and silicon are more common. Earth's crust to a depth of 16 km (10 miles) contains 8 percent aluminum. Aluminum has a strong tendency to combine with other common elements and so rarely occurs in nature in the metallic …
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bronze, alloy traditionally composed of copper and tin. Modern bronze is typically 88 percent copper and about 12 percent tin. Bronze is of exceptional historical interest and still finds wide applications. The earliest bronze artifacts were made about 4500 bce, though use of bronze in artifacts did not become common until much later, in …
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process metallurgy. metallurgy, art and science of extracting metals from their ores and modifying the metals for use. Metallurgy customarily refers to commercial as opposed to laboratory methods. It also concerns the chemical, physical, and atomic properties and structures of metals and the principles whereby metals are combined to …
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canning, Method of preserving food from spoilage by storing it in containers that are hermetically sealed and then sterilized by heat. The process was invented in 1809 by Nicolas Appert (b. c. 1750—d. 1841) of France, who used glass bottles. In the 19th century tin-coated iron cans with soldered tops, bottoms, and seams were used, but in the ...
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Chromium plating. Chromium surfaces are produced on other metals by electroplating and chromizing. There are two types of electroplating: decorative and "hard.". Decorative plate varies between 0.000254 and 0.000508 millimetre (0.00001 and 0.00002 inch) in thickness and is usually deposited over nickel. "Hard" plating is used because of ...
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In copper processing: Electrorefining. This is the final step in both pyro- and hydrometallurgical processing. In the electrolytic process, copper anodes and starting sheets are immersed in an electrolytic solution made up of copper sulfate and sulfuric acid. An electric current is passed through the solution, and copper… Read More; nickel
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magnesium processing, preparation of magnesium ore for use in various products.. Magnesium (Mg) is a silvery white metal that is similar in appearance to aluminum but weighs one-third less. With a density of only 1.738 grams per cubic centimetre, it is the lightest structural metal known. It has a hexagonal close-packed (hcp) crystalline …
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Rubber - Tapping, Coagulation, Processing: When the bark of the Hevea tree is partially cut through (tapped), a milky liquid exudes from the wound and dries to yield a rubbery film. The biological function of this latex is still obscure: it may help wound-healing by protecting the inner bark, or it may serve other biochemical functions. The latex consists of an …
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mining, process of extracting useful minerals from the surface of the Earth, including the seas. A mineral, with a few exceptions, is an inorganic substance occurring in nature that has a definite chemical composition and distinctive physical properties or molecular structure. (One organic substance, coal, is often discussed as a mineral as well.)
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Berners-Lee was the author, along with Mark Fischetti, of Weaving the Web: The Original Design and Ultimate Destiny of the World Wide Web (2000). Michael Dennis. Tim Berners-Lee, British computer scientist, generally credited as the inventor of the World Wide Web. In 2004 he was knighted by Queen Elizabeth II and received the …
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tinplate, thin steel sheet with a coating of tin applied either by dipping in molten metal or by electrolytic deposition; almost all tinplate is now produced by the latter process. Tinplate made by this process is essentially a sandwich in which the central core is strip steel. This core is cleaned in a pickling solution and then fed through ...
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Nickel processing - Extraction, Refining, Alloying: The extraction of nickel from ore follows much the same route as copper, and indeed, in a number of cases, similar processes and equipment are used. The major differences in equipment are the use of higher-temperature refractories and the increased cooling required to accommodate the higher operating …
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Dental alloys of 60–70 percent silver, 18–25 percent tin, 2–14 percent copper, and 0.5–2 percent zinc are amalgamated with varying quantities of mercury to form the filling materials for cavities in teeth. Silver and alloys of silver and copper, although stable in air, tarnish in the presence of sulfur.
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67% tin. This imitation proved so popular that by the 4th century A.D. stannum, had come to mean tin. Tin exists in two common allotropes, or forms—white tin (also called beta …
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Titanium processing - Compounds, Alloys, Oxides: Titanium oxide is widely prized for its opaque quality in coatings, plastics, high-gloss paints, ceramics, industrial enamels, paper, and inks. The compound is nontoxic and is the most common white pigment in the world. Titanium carbide (TiC) is used extensively for cutting tools because of its combination of …
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Lead processing - Mining, Concentrating, Refining: Once the ore is removed from veins (narrow channels) or lodes (roughly spherical deposits) in the Earth, usually at depths of about 60 metres, the ore is treated at concentrating mills. Here the ore is finely crushed, sometimes to particle diameters of less than 0.1 millimetre (0.004 inch), and then treated …
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Metallurgy - Alloying, Refining, Smelting: Almost all metals are used as alloys—that is, mixtures of several elements—because these have properties superior to pure metals. Alloying is done for many reasons, typically to increase strength, increase corrosion resistance, or reduce costs. In most cases, alloys are mixed from commercially pure …
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