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Описание

Copper has long been used by humans for a variety of reasons. The name copper derives from the Latin for the metal, cuprum, which is named for the Roman source, the island of Cyprus. Copper has been used in a variety of alloys; of particular importance among copper alloys is bronze, which comprised most of the tools and weapons of the age that bears its name. Brass, a copper–zinc alloy, is also highly used, for example, in brass musical instruments. Copper has also long been used as a building material, and owing to the metal’s malleability, as well as high thermal and electric conductivity, continues to find new uses. Copper and its compounds are naturally present in the earth’s crust. Natural discharges to air and water may be significant. Therefore, it is important to consider the background levels that are commonly found and distinguish these from high levels that may be found as a result of anthropogenic activity. Copper is emitted into the air naturally from windblown dust, volcanoes, and anthropogenic sources, the largest of which are being primary copper smelters and ore processing facilities. It is associated with particulate matter. The mean concentration of copper in the atmosphere is 5–200 ng m^-3.

Химические свойства

Copper is a reddish-brown metal which occurs free or in ores, such as malachite, cuprite, and chalcopyrite.
Copper is a group IB transition element on the periodic table and exists in four oxidation states: Cu0 Cu1+ (cuprous ion), Cu1+ (cupric ion), and Cu3+. In a natural state, copper is likely to be found in a variety of solid salts and compounds, but it can be found in the elemental form as well. Copper compounds generally are blue or green. The common green color of copper on exposure to air is a basic carbonate compound.

Copper is insoluble in water but readily dissolves in hot sulfuric and nitric acids. The vapor pressure is negligible at low temperatures, but in an industrial setting, in which very high temperatures are used to smelt copper ore, some potentially harmful copper fumes may be emitted. Although it not combustible in bulk, powdered copper may ignite. Fires and explosions may result from contact with oxidizing agents, strong mineral acids, alkali metals, and halogens (NIOSH, 2010).

Физические свойства

Native copper has a distinctive reddish/brown color. Its first oxidation state (+1) formscompounds with copper ions named “cuprous,” also referred to as “copper(I),” and these ionsare easily oxidized with elements in group 16 (e.g., oxygen and sulfur) and elements in group17 (the halogens).Copper’s second oxidation state (+2) forms cupric compounds, also referred to as copper(II),which are more stable than copper(I) compounds. For example, copper in both oxidationstates can combine with fluorine: for copper(I) or cuprous fluoride, Cu⁺ + F^- → CuF; and forcopper(II) or cupric fluoride, Cu²⁺ + 2F → CuF₂.Copper’s melting point is 1,083°C, its boiling point is 2,567°C, and its density is 8.94g/cm³.

Изотопы

There are 32 known isotopes of copper, ranging from Cu-52 to Cu-80. Only twoof these 32 isotopes of copper are stable, and together they make up the amount ofnatural copper found in the Earth’s crust in the following proportions: Cu-63 = 69.17%and Cu-65 = 30.83%. All the other isotopes of copper are radioactive and are artificiallyproduced with half-lives ranging from a few nanoseconds to about 61 hours.

Происхождение имени

Copper’s name comes from the Latin word cuprum or cyprium, which is related to the name “Cyprus,” the island where it was found by the ancient Romans.

Вхождение

Copper is the 26th most abundant element on Earth, but it is rare to find pure metallicdeposits. It is found in many different types of mineral ores, many of which are close to thesurface and easy to extract. It is found in two types of ores: (1) sulfide ores, such as covellite,chalcopyrite, bornite, chalcocite, and enargite; and (2) oxidized ores, such as tenorite, malachite, azurite, cuprite, chrysocolla, and brochanite.It is found in most countries of the world, but only a few high-grade deposits are costeffective to mine. Examples of some of its ores are cuprite (CuO₂), tenorite (CuO), malachite[CuCO₃ ? Cu(OH)₂], chalcocite (Cu₂S), covellite (CuS), bornite (Cu₆FeS₄), and chalcopyrite,also known as copper pyrite.Copper ores are found worldwide, in Russia, Chile, Canada, Zambia, and Zaire and, in theUnited States, in Arizona, Michigan, Montana, Nevada, New Mexico, Tennessee, and Utah.High-grade ores of 99% pure metal were found in the United States (and other countries), butmany of these native ore deposits have been mined over the past hundred years and are nowexhausted. Even so, many low-grade ores with concentrations of 10% to 80% pure copper stillexist and await a technology that will make them more profitable for exploitation.

Характеристики

Copper, a versatile metal relatively easy to find, has made it useful for humans for manycenturies. It is malleable, ductile, and easily formed into many shapes such as ingots, pipes,wire, rods, tubing, sheets, powder, shot, and coins. Although copper is resistant to weak acids,it will dissolve in strong or hot acids. It resists atmospheric corrosion better than does iron.One reason is that it forms a bluish-green film (called patina) over its surface when exposed tomoist air or seawater. This coating of copper carbonate and copper sulfate provides a protective layer for the underlying metal that makes it ideal for use on boats, roofs, pipes, and coins.The surfaces of some copper church steeples and the Statue of Liberty have now oxidized toform a pleasing patina.One of copper’s most useful characteristics is that it is an excellent conductor of electricityand heat.

История

The discovery of copper dates from prehistoric times. It is said to have been mined for more than 5000 years. It is one of man’s most important metals. Copper is reddish colored, takes on a bright metallic luster, and is malleable, ductile, and a good conductor of heat and electricity (second only to silver in electrical conductivity). The electrical industry is one of the greatest users of copper. Copper occasionally occurs native, and is found in many minerals such as cuprite, malachite, azurite, chalcopyrite, and bornite. Large copper ore deposits are found in the U.S., Chile, Zambia, Zaire, Peru, and Canada. The most important copper ores are the sulfides, oxides, and carbonates. From these, copper is obtained by smelting, leaching, and by electrolysis. Its alloys, brass and bronze, long used, are still very important; all American coins are now copper alloys; monel and gun metals also contain copper. The most important compounds are the oxide and the sulfate, blue vitriol; the latter has wide use as an agricultural poison and as an algicide in water purification. Copper compounds such as Fehling’s solution are widely used in analytical chemistry in tests for sugar. High-purity copper (99.999 + %) is readily available commercially. The price of commercial copper has fluctuated widely. The price of copper in December 2001 was about $1.50/kg. Natural copper contains two isotopes. Twenty-six other radioactive isotopes and isomers are known.

Использование

Copper is distributed widely in nature; it is the twenty-sixth most abundant element in the earth’s crust and is an essential element for many life forms. Copper is an abundant reddish, odorless metal that takes on a greenish-blue patina when exposed to the elements. It was the first metal worked by humans, and copper salts were among the first materials regularly used for therapeutic and cosmetic purposes.
Most animals require copper for certain biological processes. A deficiency of copper, as well as an excess, can have adverse health effects. The daily intake of copper in the United States ranges from 2 to 5 mg, almost all of which is excreted in the feces. Shellfish, seeds, nuts, and grains are rich sources of dietary copper. Minute amounts of cupric ion are absorbed and stored, mainly in the liver, blood, and brain. Copper is an essential cofactor in several enzyme systems (Shaligram and Campbell, 2012). Cuproenzymes catalyze important biochemical reactions, including iron absorption and hemebiosynthesis (Colotti et al., 2013).Copper deficiency may lead to anemia and neutropenia, and eventually to bone lesions resembling scurvy and to pathological fractures without hemorrhage (Kumar et al., 2005; Halfdanarson et al., 2008). Copper is also found in some intrauterine devices for the prevention of pregnancy (IPCS, 1998; Szymanski et al., 2012).

Определение

Metallic element of atomic number 29, group IB of the periodic table, aw 63.546, valences 1, 2; two stable isotopes.

Методы производства

Copper can be found free in nature (although not as commonly today). A naturally forming “patina” forms on copper in the environment (e.g., Statue of Liberty in NewYork City). The “patina” is commonly copper carbonate (from reaction with water and carbon dioxide). This thin copper carbonate layer covers exposed pure copper and prevents further oxidation. The name copper is derived from the Latin word cuprum, which, in turn, is derived from an earlier word, cyprium or “Cyprium metal.” The Romans obtained much of their copper from Cyprus, as the name implies.
Copper is found at a concentration of 50 ppm in the earth’s crust, and its concentration in seawater is 0.001–0.02 ppm. Although copper can also be obtained in an almost pure state in nature, about 85% of the copper mined today is derived from low-grade ores containing 2% or less of the metal. The major ore is chalcopyrite (CuFeS2). Ores are removed by open-pit mining as well as underground mining.

Общее описание

Reddish lustrous malleable odorless metallic solid.

Реакции воздуха и воды

Solid pieces are very slowly oxidized by air to give a green basic carbonate. Solid pieces become covered by a black oxide when heated in air. Insoluble in water.

Профиль реактивности

Copper combines violently with chlorine trifluoride in the presence of carbon [Mellor 2, Supp. 1, 1956]. Is oxidized by sodium peroxide with incandescence [Mellor 2:490-93, 1946-1947]. Forms an unstable acetylide when acetylene is passed over samples that have been heated enough to form an oxide coating. Reacts more rapidly in powdered or granular form. Subject to explosive reaction then mixed in finely divided form with finely divided bromates chlorates and iodates of barium, calcium, magnesium, potassium, sodium, or zinc; these reactions are initiated by heat, percussion, and occasionally light friction [Mellor 2:310, 1946-1947]. A solution of sodium azide in Copper pipe with lead joints formed Copper azide and lead azide, both of these compounds can detonate [Klotz, 1973].

Опасность

Copper dust and powder, as well as a few of its compounds, are flammable, or even explosivewhen ignited in contained areas. Many of copper’s compounds are extremely toxic andpoisonous either with skin contact or when inhaled or ingested and should be handled by professionals in controlled environments. Even so, both plants and animals, including humans,require traces of copper for the proper metabolism of their foods.

Промышленное использование

The most important characteristics of copperimmersion coatings are their high electricalconductivity, good lubrication properties, andunique appearance. In addition to steel, they canbe applied to brass and aluminum and to printedcircuit boards.
Because of their conductivity, copper immersioncoatings have proved particularly usefulfor printed circuits. They are not especiallynoted for their decorative appeal, but can beused in applications where a particular appearanceis required, e.g., inexpensive, decorativehardware such as casket parts. Because of theirgood lubrication properties they can also beused on steel wire in die-forming operations.

Профиль безопасности

Toxic by inhalation. Questionable carcinogen with experimental tumorigenic data. Experimental teratogenic and reproductive effects. Human systemic effects by ingestion: nausea and vomiting. See also COPPER COMPOUNDS. Liquid copper explodes on contact with water. Potentially explosive reaction with acetylenic compounds, 3-bromopropyne, ethylene oxide, lead azide, and ammonium nitrate. Iptes on contact with chlorine, chlorine trifluoride, fluorine (above 121℃), and hydrazinium nitrate (above 70'). Reacts violently with C2H2, bromates, chlorates, iodates, (Cl2 + OF2), dimethyl sulfoxide + trichloroacetic acid, ethylene oxide, H202, hydrazine mononitrate, hydrazoic acid, H2S + air, Pb(N3)2, K2O2, NaN3, Na2O2, sulfuric acid. Incandescent reaction with potassium dioxide. Incompatible with 1 -bromo-2 propyne.

Возможный контакт

Exposure to fume may occur in copper and brass plants; and during the welding of copper alloys; Metallic copper is an excellent conductor of electricity and is widely used in the electrical industry in all gauges of wire for circuitry, coil, and armature windings; high conductivity tubes; commutator bars, etc. It is made into castings, sheets, rods, tubing, and wire and is used in water and gas piping; roofing materials; cooking utensils; chemical and pharmaceutical equipment and coinage. Copper forms many important alloys: Be-Cu alloy, brass, bronze; gunmetal, bell metal; German silver; aluminum bronze, silicon bronze; phosphor bronze; and manganese bronze. Copper compounds are used as insecticides, algicides, molluscicides, plant fungicides, mordants, pigments, catalysts; as a copper supplement for pastures; and in the manufacture of powdered bronze paint and percussion caps. They are also utilized in analytical reagents, in paints for ships’ bottoms; in electroplating; and in the solvent for cellulose in rayon manufacture.

Экологическая судьба

Copper reduces glutathione, which is necessary for normal cell viability. The amino acid transferases are inhibited in the presence of excess copper; lipid peroxidation also occurs. Copper combines with thiol groups, which reduces the oxidation state II to I in copper and oxidizes the thiol groups to disulfides, especially in the cell membrane.

Перевозки

UN3089 Metal powders, flammable, n.o.s., Hazard Class: 4.1; Labels: 4.1-Flammable solid. Copper, elemental is not specifically cited in DOT’s PerformanceOriented Packaging Standards.

Несовместимости

Copper dust, fume, and mists form shock-sensitive compounds with acetylene gas, acetylenic compounds, azides, and ethylene oxides. Incompatible with acids, chemically active metals, such as potassium; sodium, magnesium, zinc, zirconium, strong bases. Violent reaction, possibly explosive, if finely divided material come in contact with strong oxidizers

Утилизация отходов

Copper-containing wastes can be concentrated through the use of ion exchange, reverse osmosis, or evaporators to the point where copper can be electrolytically removed and sent to a reclaiming firm. If recovery is not feasible, the copper can be precipitated through the use of caustics and the sludge deposited in a chemical waste landfill. Copper-containing soluble wastes can be concentrated through the use of ion exchange, reverse osmosis, or evaporators to the point where copper can be electrolytically removed and sent to a reclaiming firm. If recovery is not feasible, the copper can be precipitated through the use of caustics and the sludge deposited in a chemical waste landfill