Copper

What is Copper?

The chemical element copper has the atomic number 29 and the symbol Cu, which comes from the Latin cuprum. It is an extremely high thermal and electrical conductivity metal that is ductile, soft, and malleable. Upon initial exposure, pure copper has a pinkish-orange hue.

In addition to being used as a building material and heat and electricity conductor, copper is also a component of many metal alloys, including sterling silver, which is used in jewelry, cupronickel, which is used to make coins and marine hardware, and constantan, which is used in strain gauges and thermocouples to measure temperature.

One of the rare metals that can be found naturally in a form that is immediately useful is copper (also known as native metal).

This resulted in the employment of humans in various places as early as 8000 BC. Thousands of years later, it was the first metal to be intentionally alloyed with another metal, tin, to form bronze, circa 3500 BC; the first metal to be melted from sulfide ores, approximately 5000 BC; and the first metal to be molded into a shape in a mold, approximately 4000 BC.

Copper was mostly mined in Cyprus during the Roman era; this led to the metal’s name, cyprium (metal of Cyprus), which was later corrupted to cup rum (Latin).

This was the source of both copper and copper (Old English), with the latter spelling appearing around 1530. Copper(II) salts are often encountered compounds that have been utilized historically and widely as pigments.

They often give blue or green tints to rocks like azurite, malachite, and turquoise. Building-related copper, primarily used for roofing, oxidizes to produce a green patina known as verdigris.

Copper is occasionally used in decorative art, both as pigments in compounds and as an elemental metal.

Copper compounds find applications as fungicides, wood preservatives, and bacteriostatic agents. Since copper is a crucial component of the respiratory enzyme complex cytochrome c oxidase, it is required as a trace mineral by all living things.

The blood pigment hemocyanin in mollusks and crustaceans contains copper, whereas hemoglobin in fish and other vertebrates is iron-complexed. Copper is mostly found in the liver, muscles, and bones of people.

Between 1.4 and 2.1 milligrams of copper are found in each kilogram of body weight in an adult.

Characteristics

Physical

Group 11 of the periodic table contains copper, silver, and gold. These three metals are distinguished by great ductility as well as electrical and thermal conductivity. They each have one s-orbital electron on top of a filled d-electron shell.

These elements’ packed d-shells have minimal effect on interatomic interactions, which are mostly mediated by metallic connections between s-electrons.

Copper’s metallic bonds are weak and lack a covalent character, in contrast to metals having incomplete d-shells. This finding explains why single copper crystals have a high degree of ductility and a low hardness.

In theOn a macroscopic level, the material becomes harder when prolonged crystal lattice imperfections, like grain boundaries, are introduced because they impede the material’s ability to flow under applied stress.

Because of this, fine-grained polycrystalline copper is typically supplied, which is stronger than monocrystalline copper.

Copper’s high electrical conductivity (59.6×10⁶ S/m) and high thermal conductivity, which is second only to silver among pure metals at ambient temperature, can be partially attributed to its softness.

This is due to the fact that the scattering of electrons on thermal vibrations of the lattice, which are very mild in soft metal, is the primary source of resistance to electron transport in metals at ambient temperature.

In open air, copper has a maximum allowable [possible?] current density of about 3.1×10⁶ A/m2, beyond which it overheats.

Among the metallic elements, copper is one of the few that have a natural hue other than silver or gray. When pure copper is exposed to air, its orange-red color changes to a reddish tarnish.

This is because the metal absorbs the higher-frequency green and blue hues because of its low plasma frequency, which is seen in the visible spectrum’s red region.

Similar to other metals, galvanic corrosion will happen when copper comes into contact with another metal in the presence of an electrolyte.

Chemical

Unlike rust, which forms on iron in wet air, copper does not react with water. However, it does slowly react with ambient oxygen to generate a layer of brown-black copper oxide, which passivates the underlying metal, preventing further corrosion.

Older copper constructions, like the Statue of Liberty’s roof and the roofs of many older buildings, frequently have a green layer of verdigris (copper carbonate) on them.

When exposed to certain sulfur compounds, copper tarnishes and forms different copper sulfides as a result of the reaction.

Isotopes

Copper has 29 different isotopes. Both ⁶³Cu and ⁶⁵Cu have spins of 3⁄2, and both are stable. Of the naturally occurring copper, ⁶³Cu makes up about 69%. With a half-life of 61.83 hours, ⁶⁷Cu is the most stable isotope among the radioactive ones.

With a half-life of 3.8 minutes, 68m Cu is the longest-living of the seven metastable isomers that have been identified.

Mass-number-below 64 isotopes decay by β⁺, while mass-number- above 64 isotopes decay by β⁻. ⁶⁴Cu decays in both directions and has a half-life of 12.7 hours.

There are several important uses for ⁶²Cu and ⁶⁴Cu. For positron emission tomography, ⁶²Cu is employed as a radioactive tracer in ⁶²Cu Cu-PTSM.

Occurrence

Massive stars generate copper, which is found in the crust of the Earth at a concentration of roughly 50 parts per million (ppm).

Copper can be found in nature in many different forms, such as native copper, copper sulfides like bornite, chalcopyrite, digenite, covellite, and chalcocite, copper sulfosalts like enargite and tetrahedrite-tennantite, copper carbonates like malachite and azurite, and copper(I) or copper(II) oxides like tenorite and cuprite, respectively.

420 tons was the greatest mass of elemental copper ever found, and it was discovered in 1857 on the US Keweenaw Peninsula in Michigan.

The largest known single crystal of native copper, which is polycrystal, measures 4.4 cm by 3.2 cm by 3.2 cm.

With a 50 ppm abundance, copper ranks as the 25th most prevalent element in the crust of Earth, behind zinc’s 75 ppm and lead’s 14 ppm.

In freshwater, 2 μg/L, 0.5 μg/L, 150 mg/kg in soil, 30 mg/kg in vegetation, and 1 ng/m³ in the atmosphere are the typical background values of copper.

Production

The majority of copper is recovered or mined as copper sulfides from sizable open pit mines in porphyry copper deposits, which range in copper content from 0.4% to 1.0%.

Chuquicamata in Chile, Bingham Canyon Mine in Utah, and El Chino Mine in New Mexico are among the locations.

As per the British Geological Survey, Chile accounted for at least one-third of global copper production in 2005, with the United States, Indonesia, and Peru following closely behind.

Moreover, copper can be extracted using the in-situ leach method. A number of locations in Arizona are seen to be excellent fits for this technique.

The quantity of The amount of copper being used is growing, but not nearly enough to enable all nations to utilize it at the levels of the developed world.

Polymetallic nodules found around 3000–6500 meters below sea level in the Pacific Ocean, are an alternate source of copper that is now being investigated for collection. Other precious metals like nickel and cobalt can be found in these nodules.

Reserves and Prices

Although copper has been used for at least 10,000 years, since 1900, more than 95% of the copper that has ever been mined and smelted has been taken out.

\Like with many other natural resources, there is a significant amount of copper on Earth overall. At the current rate of extraction, the top kilometer of Earth’s crust contains approximately 1014 tons of copper or over 5 million years’ worth.

Only a small portion of these reserves, though, are commercially feasible given current costs and technological advancements.

The estimated length of time that copper reserves may be mined ranges from 25 to 60 years, depending on key factors including growth rate.

In the current world, recycling is a key source of copper. Copper’s price fluctuates a lot. Following an unanticipated peak in 2022, the price dropped.

Methods

Sulfides make up the vast majority of copper ores. The sulfides bornite (CuFeS₂), chalcopyrite (Cu₅FeS₄), and, to a lesser degree, covellite (CuS) and chalcocite (Cu₂S) are common ores.

These ores are found at less than 1% Cu. The ore must be concentrated, which is done by froth flotation after comminution.

Two simplified equations can be used to describe the smelted concentrate, which is the residual portion.

2 Cu₂S + 3 O₂ → 2 Cu₂O + 2 SO₂

When heated, cuprous oxide and cuprous sulfide combine to form blister copper.

2 Cu₂O + Cu₂S → 6 Cu + 2 SO₂

After roasting, matte copper (about 50% Cu by weight) is obtained, and electrolysis is used to purify it.

Gold and platinum are among the additional metals that can occasionally be obtained during the electrolysis process, depending on the ore.

Oxides are a different family of ores than sulfides. These oxides provide around 15% of the world’s copper supply.

Oxides are beneficiated by extraction using solutions of sulfuric acid, which is followed by electrolysis. Parallel to the previously described process for “concentrated” sulfide and oxide ores, copper is extracted from heaps and tailings from mines.

Numerous techniques are employed, such as leaching using ferric chloride, ammonia, and sulfuric acid. There are biological approaches as well.

Copper is primarily obtained from recycling. Because copper is typically used in its metallic state, recycling is made easier.

A normal car in 2001 had between 20 and 30kg of copper in it. Recycling typically starts with a blast furnace-based melting procedure. Polymetallic nodules, which have an estimated content of 1.3%, are a possible source of copper.

Flowchart of copper refining (Uralelektromed)

1. Smelting
2. Slag removal 
3. Reverberatory furnace 
4. Blister copper 
5. Copper casting of anodes
6. spoke wheel
7. Anode removal apparatus
8. Anodes launch
9. Train vehicles
10. Moving to the storage facility

Recycling

Copper may be recycled without sacrificing quality, just like aluminum, in both its raw and finished forms.

After iron and aluminum, copper is the third most recycled metal in terms of volume. Approximately 80% of all copper extracted to date remains in operational use.

The Metal Stocks in Society report by the International Resource Panel states that the world’s per capita copper stock used in society is between 35 and 55 kg.

Compared to less developed countries (30–40 kg per capita), more developed countries (140–300 kg per capita) have a greater share of this.

Although recycling copper involves fewer processes, the procedure is essentially the same as that of extracting copper.

Lower-purity scrap copper is refined by electroplating in a sulfuric acid bath; high-purity scrap copper is melted in a furnace, reduced, and cast into billets and ingots.

Environmental Impacts

According to estimates, the environmental cost of mining copper in 2019 was 3.7 kg CO2eq per kilogram of copper.

According to Codelco, a significant producer in Chile, its fine copper emissions in 2020 amounted to 2.8t CO2eq per ton (2.8 kg CO2eq per kilogram).

The company’s electricity use, particularly when it comes from fossil fuels, and the engines used in the extraction and processing of copper are the main sources of greenhouse gas emissions.

Businesses that mine land frequently handle trash improperly, permanently sterilizing the region. Not to mention, the surrounding trees and rivers suffer as well.

One area where land is overexploited by mining firms is the Philippines. Nearby water characteristics have been drastically affected by copper mining waste in Valea Şesei, Romania.

The water in the impacted areas has heightened electrical conductivity levels between 280 and 1561 mS/cm and is extremely acidic, with a pH range of 2.1–4.9. The environment is unfriendly for fish due to these alterations in water chemistry, therefore making the water unfit for aquatic life.

Alloys

Many copper alloys with significant applications have been developed. Copper and zinc are combined to create brass.

Although copper alloys, such as aluminum bronze, are commonly referred to as bronze, the term can also refer to any copper alloy.

One of the most crucial ingredients in the silver and karat gold solders used in the jewelry industry is copper, which alters the alloy’s color, hardness, and melting point.

A tiny amount of copper and other metals are alloyed with tin to create certain lead-free solders. Low-denomination coins frequently have cupronickel, an alloy of copper and nickel, for the exterior cladding.

The homogenous composition of the US five-cent coin, now known as nickel, is made up of 75% copper and 25% nickel.

Before cupronickel, which was widely used by nations in the second half of the 20th century, copper and silver alloys were also used.

Up until 1965, the United States used an alloy of 90% silver and 10% copper for its coins; after that, all of its coins—aside from the half-dollar—were debased to an alloy of 40% silver and 60% copper.

Although it is susceptible to the sulfides occasionally found in contaminated harbors and estuaries, the alloy consisting of 90% copper and 10% nickel, which is notable for its resistance to corrosion, is utilized for a variety of products exposed to seawater.

Copper alloys that contain aluminum (approximately 7%) are employed as ornaments and have a golden hue. Shakudō is a decorative copper alloy from Japan that has a small amount of gold (4–10%) and can be patinated to a dark blue or black hue.

Compounds

A wide range of compounds are formed by copper, typically with oxidation states of +1 and +2, which are referred to as cuprous and cupric, respectively. Numerous chemical and biological processes are aided by or catalyzed by copper compounds.

Binary Compounds

Similar to other elements, binary compounds—those with just two elements—are the most basic forms of copper.

Oxides, sulfides, and halides are the main examples of these types of compounds. There are known forms of cuprous and cupric oxides. Important examples of the various copper sulfides are copper(I) sulfide (Cu₂S) and copper monosulfide (CuS).

It is known that cupric halides contain fluorine, chlorine, and bromine as well as cuprous halides containing fluorine, chlorine, and iodine. The only products of attempts to make copper(II) iodide are copper(I) iodide and iodine.

2 Cu²⁺ + 4 I⁻ → 2 CuI + I₂

Coordination Chemistry

Coordination complexes are formed by copper and ligands. Copper(II) occurs as [Cu(H₂O)₆]²⁺ in aqueous solution. Of all the transition metal aqua complexes, this one has the fastest water exchange rate—the rate at which water ligands attach and detach.

Light blue solid copper(II) hydroxide precipitates when aqueous sodium hydroxide is added. Here’s an equation that has been simplified

Cu²⁺ + 2 OH⁻ → Cu(OH)₂
There is a similar precipitate produced by aqueous ammonia. Tetraammine copper (II) is formed when the precipitate dissolves insufficient ammonia.

Cu(H₂O)₄(OH)₂ + 4 NH₃ → [Cu(H₂O)₂(NH₃)₄]²⁺+ 2 H₂O + 2 OH⁻

Copper(II) carbonate, copper(II) nitrate, and copper(II) acetate are just a few of the several different oxyanions that can form complexes.

The most well-known copper compound in the laboratory is blue crystalline pentahydrate, which is formed by copper(II) sulfate.

It is a component of the Bordeaux combination, a fungicide. Cupric salts and polyols, which are substances with several alcohol functional groups, typically interact.

For instance, reducing sugars are tested with copper salts. In particular, the presence of sugar is indicated by a color shift from blue Cu(II) to reddish copper(I) oxide using Fehling’s solution and Benedict’s reagent.

Cellulose is dissolved by Schweizer’s reagent and similar compounds containing ethylenediamine and other amines.

Cysteine and other amino acids combine with copper(II) to generate incredibly stable chelate complexes, which can take the shape of metal-organic biohybrids (MOBs).

There are numerous wet-chemical assays for copper ions available. One of them uses potassium ferricyanide, which when combined with copper(II) salts, produces a vivid blue precipitate.

Organocopper Chemistry

Organocopper compounds are those that have a carbon-copper bond in them. They have numerous applications in chemistry and are highly reactive with oxygen, forming copper(I) oxide.

Grignard reagents, terminal alkynes, or organolithium reagents are used to synthesize them from copper(I) compounds; the final reaction mentioned above, for instance, yields a Gilman reagent.

To create coupling, they can be substituted with alkyl halides. As a result, they play a significant role in the field of organic synthesis.

Although it is an intermediate in reactions like the Cadiot– Chodkiewicz coupling and the Sonogashira coupling, copper(I) acetylide is extremely shock-sensitive.

Organocopper compounds can also be used for carbocupration of alkynes and conjugate addition to enones. When amine ligands are present, copper(I) can form a range of weak complexes with alkenes and carbon monoxide.

Copper(III) and Copper(IV)

The most common form of copper(III) is an oxide. Potassium cuprate, or KCuO₂, a blue-black solid, is an easy example. The cuprate superconductors are the copper(III) compounds that have been explored the most.

Copper oxide of yttrium barium (YBa₂Cu₃O₇) has two centers of concentration: Cu(II) and Cu(III). Fluoride, a very basic anion that is similar to oxide, is known to stabilize metal ions in high oxidation states.

There are known fluorides of copper(III) and even copper(IV), K₃CuF₆ and  Cs₂CuF6, respectively. Certain copper proteins combine with copper(III) to generate oxo complexes.

Tetrapeptides have deprotonated amide ligands that stabilize purple-colored copper(III) complexes.

Copper(III) complexes are also discovered as intermediates in organocopper compound reactions, such as the Kharasch–Sosnovsky reaction.

History

A timeline of copper’s uses throughout the past 11,000 years shows how this metal has advanced human civilization.

Prehistoric

Copper Age

Copper was known to some of the earliest recorded civilizations and occurs naturally as native metallic copper.

In the Middle East, copper has been used since 9000 BC. An 8700 BC copper pendant was discovered in northern Iraq. Research points to gold and meteoric iron being the only metals used by humans prior to copper, not smelted iron.

It is believed that the development of copper metallurgy went as follows: cold-working native copper first, followed by annealing, smelting, and eventually lost-wax casting.

All four of these methods first emerge in southeastern Anatolia around 7500 BC, at the start of the Neolithic period.

Smelting copper was separately developed in several locations. It was most likely found in West Africa in the ninth or tenth century AD, in Central America circa 600 AD, and in China prior to 2800 BC.

From an amulet discovered at Mehrgarh, Pakistan, an ancient lost wax-casting copper is known to exist as early as 4000 BC.

Carbon dating places the invention of investment casting in Southeast Asia between 4500 and 4000 BC, and the mining of Alderley Edge in Cheshire, UK, between 2280 and 1890 BC.

The male Ötzi the Iceman, who lived between 3300 and 3200 BC, was discovered with an axe that had a 99.7% pure copper head; elevated levels of arsenic in his hair point to possible involvement in copper smelting.

The evolution of other metals has benefited from experience with copper; iron smelting was discovered as a result of copper smelting.

Between 6500 and 3000 BC, production in the Old Copper Complex in Wisconsin and Michigan began. A spearpoint made of copper discovered in Wisconsin has been dated to 6500 BC.

It has been determined through radiometric dating that the Old Copper Complex indigenous peoples of North America’s Great Lakes region used copper as early as 7500 BC.

It’s possible that native Americans living near the Great Lakes in North America were also miners. Copper at this period, making it among the world’s earliest documented instances of copper extraction.

Prehistoric lead poisoning from Michigan lakes provides evidence that the area’s inhabitants started mining copper around 6000 BC.

There is evidence that during the Bronze Age in the Old Copper Complex of North America, ornamental copper objects were produced more frequently than utilitarian copper objects, which became less and less useful.

Bronze Age

Around 5500 BC, natural bronze—a kind of copper derived from ores high in silicon, arsenic, and (occasionally) tin—began to be widely used in the Balkans.

About 4,000 years after copper smelting was discovered and 2000 years after “natural bronze” had become widely used, the process of alloying copper with tin to create bronze was first used. From the Vinča culture, bronze artifacts date back to 4500 BC.

Copper and bronze alloy artifacts from Sumerian and Egyptian cultures date back to 3000 BC. Cuprorivaite, often known as Egyptian Blue, is a synthetic pigment that was first used in ancient Egypt in approximately 3250 BC and includes copper.

The Romans were aware of how Egyptian blue was made, but by the fourth century AD, the pigment had become obsolete and the method of production had been forgotten.

The blue pigment known to the Romans as caeruleum was reportedly composed of copper, silica, lime, and natron.

Around 3700–3300 BC, the Bronze Age started in Southeast Europe and about 2500 BC in Northwestern Europe. It came to an end in the year 600 BC in Northern Europe and 2000–1000 BC in the Near East with the start of the Iron Age.

The Chalcolithic period (copper-stone) was the name given to the period when stone and copper implements were used to move from the Neolithic to the Bronze Age.

The phrase has increasingly lost popularity. because the Chalcolithic and Neolithic epochs are coterminous at both ends in several regions of the planet.

Brass is a much more modern alloy made of copper and zinc. Although the Greeks were aware of it, the Roman Empire saw its use as a vital addition to bronze.

Ancient and Post-Classical

Halos (χαλκός) was the Greek term for copper. For the Romans, Greeks, and other ancient peoples, it was a valuable resource.

It was called Aes Cyprium in Roman times, from the Latin aes, which means copper alloys generally, and Cyprium, which comes from Cyprus, a region with abundant copper mines. The English copper came from the term being reduced to cuprum.

Because of its glossy beauty and long history of use in the creation of mirrors, copper was symbolized in mythology and alchemy by Aphrodite (Venus in Rome); Cyprus, the source of copper, was considered holy by the goddess.

Venus was assigned to copper because of its association with the goddess and because it was the brightest heavenly body after the Sun and Moon, making copper the most lustrous and desirable metal after gold and silver.

The seven heavenly bodies known to the ancients were also associated with the seven metals known in antiquity.

As early as 2100 BC, copper was first mined in ancient Britain. Into the late Bronze Age, mining was still going on at the Great Orme, the greatest of these mines.

Supergene ores, which were simpler to process, appear to have been the only ones that were mined extensively. Despite widespread tin mining in the area, Cornwall’s significant copper reserves appear to have remained mostly unexplored—possibly due to social and political factors more than technological advancements.

Between 800 and 1600 AD, native copper in North America is believed to have been mined using rudimentary stone tools from locations on Isle Royale.

Around the year 1000–1300 AD, the North American city of Cahokia was engaged in the practice of copper annealing.

Several beautiful copper plates from this era (1000–1300 AD), referred to as the Mississippian copper plates, have been discovered in North America in the vicinity of Cahokia.

The Wulfing cache and Etowah plates, among other locations in the Midwest and Southeast of the United States, were believed to have received the copper plates after being produced at Cahokia.

The oldest known copper artifact unearthed in the Andes is a 1000 BC copper mask from South America that was recovered in the Argentinean Andes.

Although early copper metallurgy in pre-Columbian America has often been attributed to Peru, the copper mask from Argentina indicates that the Cajón del Maipo in the southern Andes was also a significant hub for early copper workings in South America.

Around the year 1000 AD, copper metallurgy was booming throughout South America, especially in Peru.

Although 15th-century burial ornamentals made of copper have been found, commercial manufacture of the metal did not begin until the early 20th century. Copper has played a significant cultural significance, especially in currency.

In the sixth and third centuries BC, copper lumps were employed as currency by the Romans. Initially, the copper itself held value, but with time, its appearance and shape gained more significance.

While Octavianus Augustus Caesar’s coins were constructed of Cu-Pb-Sn alloys, Julius Caesar’s coins were made of brass.

Roman copper mining and smelting operations reached a scale unparalleled until the Industrial Revolution, with an estimated yearly output of about 15,000 t; the most heavily mined provinces were those of Hispania, Cyprus, and Central Europe.

The Corinthian bronze gates of the Temple of Jerusalem were gilded with gold. Alchemy is believed to have started in Alexandria, where the practice was most common.

Copper was utilized for surgical instruments and other medical equipment in the holistic medicinal science of Ayurveda in ancient India.

Copper was used by the ancient Egyptians (c. 2400 BC) to alleviate headaches, burns, and itching, as well as to sterilize wounds and drink water.

Modern

The Great Copper Mountain mine was in operation near Falun, Sweden, from the tenth century until 1992.

In the seventeenth century, it met two-thirds of Europe’s copper needs and contributed to the financing of several of Sweden’s wars. It was called the country’s treasury; Sweden’s currency was backed by copper.

Copper is used in currency, roofing, and daguerreotype photography technology. Copper is still utilized in many different kinds of architecture. It was employed in Renaissance sculpture and in the building of the Statue of Liberty.

The British Admiralty invented the practice of protecting ships’ underwater hulls with copper plating and copper sheathing in the 18th century, and it was widely utilized thereafter.

The first electroplating plant in use today was Norddeutsche Affinerie in Hamburg, which began operations in 1876.

In the process of figuring out the metal’s atomic mass, German scientist Gottfried Osann created powder metallurgy in 1830.

It was at this time that bell tones were found to be influenced by the type and quantity of alloying elements (such as tin) added to copper.

Between one-third and half of the world’s newly mined copper was produced in the United States during the period from the 1880s to the Great Depression of the 1930s, when demand for copper increased during the Age of Electricity.

Important districts included the native copper-rich Keweenaw district in northern Michigan. In the late 1880s, however, these deposits were surpassed by the massive sulfide deposits of Butte,

Montana, which was surpassed in turn by the porphyry deposits of the Southwest, particularly in Bingham Canyon, Utah, and Morenci, Arizona.

Mass production was made possible with the introduction of open-pit steam shovel mining as well as advancements in smelting, refining, flotation concentration, and other processing procedures.

Arizona was number one at the beginning of the 20th century, then Montana, Utah, and Michigan.

The energy-efficient method known as flash smelting, which was created by Outokumpu in Finland and used for the first time at Harjavalta in 1949, is responsible for half of the world’s primary copper production.

Established in 1967 by Chile, Peru, Zambia, and Zaire, the Intergovernmental Council of Copper Exporting Countries functioned in the copper market similarly to OPEC in the oil sector.

However, it was never able to attain the same level of influence, mainly due to the absence of the United States, the second-largest producer, from its membership. The council was eventually dissolved in 1988.

Applications

Copper is mostly used in industrial machinery (15%), roofing and plumbing (20%), and electrical wire (60%).

Copper is usually used as a pure metal, although it is also employed (5% of total use) in alloys like brass and bronze when higher hardness is needed.

Boat hulls have been painted with copper paint for over 200 years to suppress the growth of algae and shellfish.

Fungicides and dietary supplements use a small portion of the world’s copper supply. Although alloys are chosen for high machinability when producing complicated pieces, copper may be machined.

Wire and Cable

With the exception of overhead electric power transmission, where aluminum is frequently favored, copper continues to be the primary electrical conductor despite competition from other materials.

Numerous kinds of electrical equipment, telecommunications, electronics circuitry, power distribution, power transmission, and power generation all need copper wire. Electrical wire is the biggest market for the copper industry.

Power distribution cables and structural power wiring are examples of this. automobile wire and cable, communications cable, appliance wire, and magnet wire.

Approximately 50% of all copper that is mined is utilized to make cable and wire conductors. Copper wiring is used in many electrical

devices due to their many intrinsic advantages, including low thermal expansion, high thermal conductivity, tensile strength, ductility, creep (deformation) resistance, corrosion resistance, ease of soldering, malleability, and ease of installation.

Aluminum wiring briefly took the role of copper wiring in many American home construction projects between the late 1960s and the late 1970s. After several home fires were linked to the new wiring, the industry switched back to copper.

Electronics and Related Devices

Copper is used in integrated circuits and printed circuit boards more often than aluminum due to its greater electrical conductivity; copper is also used in heat sinks and heat exchangers because of its superior heat dissipation capabilities. Copper is used in waveguides for microwave radiation, electromagnets, vacuum tubes, cathode ray tubes, and magnetrons in microwave ovens.

Electric Motors

The higher conductivity of copper increases electrical motor efficiency. This is significant because 69% of the electricity consumed by industry and 43-66% of the world’s electricity consumption are attributed to motors and motor-driven devices.

Increases in the mass and cross-section of copper in a coil result in higher motor efficiency.

The National Electrical Manufacturers Association (NEMA) premium efficiency standards are being met and exceeded by general-purpose induction motors thanks to a new technology called copper motor rotors, which is intended for motor applications where energy reductions are primary design objectives.

Renewable Energy Production

Solar, wind, tidal, hydro, biomass, and geothermal energy are examples of renewable energy sources that have grown to represent important segments of the energy industry.

The rising price of fossil fuels and concerns about their environmental effects have led to a major decrease in the usage of these sources, which has resulted in their rapid expansion in the 21st century.

An essential component of these renewable energy systems is copper. In renewable energy systems, copper is used up to five times more frequently than it is in conventional power generation, which includes nuclear and fossil fuel facilities.

Second only to silver in terms of electrical and thermal conductivity among engineering metals, copper is used in electrical systems to transfer and create energy with great efficiency and little negative environmental impact.

Facility planners and engineers weigh the capital investment costs of materials against the operational savings resulting from their electrical energy efficiency over the course of their usable lives, as well as maintenance costs when selecting electrical conductors.

Frequently, copper does well in these computations. The amount of copper required to install one megawatt of new power-generating capacity is measured by a factor known as “copper usage intensity.

To avoid shortages of particular materials, engineers and product specifiers are aiming to build a new renewable power plant.

Despite the fact that the world’s refined consumption has more than tripled in the past 50 years, the United States Geological Survey reports that in-ground copper reserves have climbed more than 700% since 1950, from roughly 100 million tonnes to 720 million tonnes in 2017.

Resources for copper are thought to surpass 5,000 million tonnes. More than thirty percent of the copper installed between 2007 and 2017 came from recycled sources, supporting the supply from copper extraction. More than any other metal, it is recycled.

Architecture

Since ancient times, copper has been utilized as a strong, weatherproof, and corrosion-resistant building material.

Copper has been used for hundreds or thousands of years to make doors, vaults, flashings, rain gutters, downspouts, domes, spires, and vaults.

In contemporary architecture, copper is being used for more than only exterior and interior wall cladding. It is also used for radio frequency shielding, building expansion joints, and antibacterial and decorative inside products like countertops, elegant handrails, and bathroom fittings.

Copper is an excellent choice for architectural applications due to its low heat transfer, lightweight, lightning protection, and recyclability.

The unique green patina of the metal has long been prized by designers and architects. The final patina is a very strong covering that shields the underlying metal from additional weathering by being extremely resistant to atmospheric corrosion.

It can consist of a combination of different amounts of sulfate and carbonate compounds, depending on the surrounding environment, such as acid rain that contains sulfur.

It is possible to “finish” architectural copper and its alloys to give them a specific appearance, texture, or color.

Coatings, chemical coloring, and mechanical surface treatments are examples of finishes. Copper can be welded, and it has good brazing and soldering qualities; gas metal arc welding yields the best results.

Antibiofouling

Because copper is biostatic, it inhibits the growth of bacteria and many other types of life. Because of this, it has been used for a long time to line ship sections in order to prevent barnacles and mussels.

Although it was once used pure, paint based on copper and muntz metal has since taken its place.

Copper alloys have also gained importance as netting materials in the aquaculture industry due to their strong structural and corrosion-resistant qualities in marine territories, as well as their antimicrobial properties that prevent biofouling even in harsh conditions (see Copper alloys in aquaculture).

Antimicrobial

Numerous microbes, including E. Coli O157:H7, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus, Clostridium difficile, influenza A virus, adenovirus, SARS-CoV-2, and fungus, are destroyed by the inherent characteristics of copper-alloy contact surfaces.

Before contemporary science discovered copper’s antibacterial qualities, Indians have been preserving water in copper pots since ancient times.

When routinely cleaned, certain copper alloys have been shown to eradicate over 99.9% of pathogenic bacteria in as little as two hours.

The registrations of these copper alloys as “antimicrobial materials with public health benefits” have been accepted by the US Environmental Protection Agency (EPA).

This permission permits producers to legally assert the benefits of their products’ public health that are made of registered alloys.

Furthermore, a plethora of antimicrobial copper devices, including computer keyboards, health club equipment, over-bed tables, door knobs, faucets, sinks, and cart handles, have been authorized by the EPA and manufactured from these alloys.

Hospitals utilize copper doorknobs to limit the spread of illness, and Legionnaires’ disease is one such illness. suppressed in plumbing systems by copper tubing. Healthcare facilities in the US, the UK,

Ireland, Japan, Korea, France, Denmark, and Brazil are now installing antimicrobial copper alloy products. In addition, the Santiago, Chile subway system installed copper-zinc alloy handrails in about 30 stations between 2011 and 2014.

Copper can be used with textile fibers to make materials that are antibacterial and protective.

Copper Demand

It is anticipated that global production will reach around 23 million metric tons in 2023. As more and more energy is being converted to electricity, there is a growing demand for copper. China supplies more than half of the demand.

Other metals can be used in place of certain ones. Aluminum wire was used in place of aluminum wire in many applications, but poor design created fire hazards. Since then, the safety concerns have been

resolved by using larger diameter aluminum wire (#8AWG and larger), and copper wiring is still replaced with well-constructed aluminum wiring.

For instance, the Airbus A380 transmits electrical power using aluminum wire rather than copper wire.

Speculative investing

Given its anticipated rise in consumption due to global infrastructure growth and its significance in the production of wind turbines, solar panels, and other renewable energy sources, copper might be considered a speculative investment.

The average amount of copper in electric cars is 3.6 times more than in conventional automobiles, which is another factor contributing to the anticipated increases in demand. However, the impact of electric cars on copper demand is argued.

Some investors use futures, exchange-traded funds, and equities of copper mining companies. Some people choose to store actual copper in the shape of rounds or bars, even though these are typically more expensive than precious metals.

Old copper wire, copper tubing, or US pennies manufactured before 1982 can be stored by those who wish to avoid paying the premiums associated with copper bullion.

Folk Medicine

Jewelry made of copper is frequently used, and there is a folktale that copper bracelets help with the symptoms of arthritis.

Between the copper bracelet and the control (non-copper) bracelet, no differences were observed in two trials: one for rheumatoid arthritis and the other for osteoarthritis.

There is no proof that copper may enter the body through the skin. If it were, copper poisoning could result.

Degradation

Solid copper can be mobilized by Pseudomonas fluorescens and Chromobacterium violaceum as a cyanide compound.

Fericoid mycorrhizal fungi linked to Calluna, Erica, and Vaccinium are capable of proliferating in copper-rich metalliferous soils.

Suillus luteus, an ectomycorrhizal fungus, shields young pine plants against copper poisoning. Aspergillus niger was discovered to be growing in a sample of gold mining solution, and it was discovered to contain cyano complexes of various metals, including iron, zinc, copper, silver, and gold. In addition, the fungus contributes to the solubilization of sulfides of heavy metals.

Biological Role

Biochemistry

Copper(I) and Cu(II) interconversion is easily exploited by copper proteins, which play a variety of roles in biological electron and oxygen transport.

For all eukaryotes to engage in aerobic respiration, copper is necessary. It is present in cytochrome c oxidase, the final protein involved in oxidative phosphorylation, in mitochondria.

The protein called cytochrome c oxidase is responsible for binding O₂ between copper and iron. It does this by giving the O₂ molecule eight electrons, which splits it into two molecules of water. Superoxide dismutases are proteins that catalyze the

breakdown of superoxides by disproportionating them into oxygen and hydrogen peroxide. Copper is also present in many of these proteins.
Cu²⁺-SOD + O₂⁻ → Cu⁺-SOD + O₂  (superoxide oxidation; copper reduction)
Cu⁺-SOD + O₂⁻ + 2H⁺ → Cu²⁺-SOD + H₂O₂ (superoxide oxidation; copper reduction)

In the majority of mollusks and certain arthropods, like the horseshoe crab (Limulus polyphemus), the oxygen is carried by the protein hemocyanin.

\These species have blue blood instead of the red blood of hemoglobin based on iron because hemocyanin is blue.

Hemocyanin is structurally related to laccases and tyrosinases. These proteins hydroxylate substrates rather than reversibly bind oxygen, as demonstrated by their involvement in the creation of lacquers.

The introduction of oxygen into Earth’s atmosphere marked the beginning of copper’s biological function. Some copper proteins—the so-called “blue copper proteins” among them—do not interact with substrates directly, making them non-enzymes.

Electron transfer is the method used by these proteins to transport In nitrous-oxide reductase, a distinct tetranuclear copper center has been discovered. Research has been done on the potential applications of chemical compounds created to treat Wilson’s illness in cancer therapy.

Nutrition

While not all bacteria require copper, it is a necessary trace element in plants and animals. Copper levels in the human body range from 1.4 to 2.1 milligrams per kilogram of body mass.

Absorption

After being absorbed in the stomach, copper is carried to the liver and attached to albumin. Most of the copper in the blood is carried by the protein ceruloplasmin, which is involved in a second phase of copper distribution to other tissues after processing in the liver.

Ceruloplasmin is an exceptionally well-absorbed copper supplement that also contains the copper secreted in milk.

The body typically excretes excess copper via bile, which transports some copper from the liver that is not subsequently reabsorbed by the intestine.

Copper normally undergoes enterohepatic circulation in the body (approximately 5 mg per day, compared to about 1 mg per day absorbed in the diet and excreted from the body).

Dietary Recommendations

In 2001, the U.S. Institute of Medicine (IOM) revised the recommended dietary allowances (RDAs) and estimated average needs (EARs) for copper.

When there is not enough evidence to determine EARs and RDAs, an estimate known as Adequate Intake (AI) is used instead of them. For males and females aged 0–6 months, the AIs for copper are 200 μg, and for those aged 7–12 months, the AIs are 220 μg.

The recommended daily allowances (RDAs) for copper for both genders are 340 μg for ages 1-3, 440 μg for ages 4-8, 700 μg for ages 9-13, and 890 μg for ages 14-18.aged 19 years and above, and 900 μg of copper for those who are older. One thousand μg for pregnancy.

A lactation dose of 1,300 μg. The IOM also determines acceptable upper intake levels (ULs) for vitamins and minerals when there is sufficient evidence to support a claim. The daily limit (UL) for copper is 10 mg.

All of the EARs, RDAs, AIs, and ULs are referred to collectively.The European Food Safety Authority (EFSA), which employs Population Reference Intake (PRI) rather than RDA and calls the entire data collection “Dietary Reference Values,” Average Requirement (EAR) in place of EAR.

AI and UL have the same meanings as they have in the US. The daily doses of AIs for men and women who are 18 years of age and above are 1.6 and 1.3 mg, respectively. Pregnancy and lactation AI dosage is 1.5 mg/day. AIs rise with age in children aged 1 to 17 years, from 0.7 to 1.3 mg/day.

The AIs here surpass the RDAs in the US. After reviewing the identical safety query, the European Food Safety Authority determined that 5 mg/day was the acceptable limit, which is half of the US number.

To comply with U.S. The quantity in a serving is expressed as a percentage of the Daily Value (%DV) in accordance with standards for food and dietary supplement labeling.

100% of the Daily Value for copper labeling was 2.0 mg; however, starting on May 27, 2016, it was changed to 0.9 mg to conform to the RDA. The historical and present adult daily values are shown in a table.

Deficiency

Copper deficiency can result in anemia-like symptoms, neutropenia, bone abnormalities, hypopigmentation, poor growth, an increased risk of infections, osteoporosis, hyperthyroidism, and irregularities.

The metabolism of glucose and cholesterol because of its function in aiding the absorption of iron. On the other hand, tissues within the body accumulate copper due to Wilson’s disease.

Low levels of ceruloplasmin, red blood cell superoxide dismutase, and plasma or serum copper can all be used to identify severe deficiency; these tests are not sensitive to marginal copper status.

Replication has not verified the findings, although it has been suggested that the “cytochrome c oxidase activity of leucocytes and platelets” is another contributing element in deficiency.

Toxicity

Acute copper toxicity has been reported in humans after gram-sized amounts of different copper salts were consumed during suicide attempts; this may be because redox cycling produces reactive oxygen species, which harm DNA.

Animals exposed to copper salts at equivalent concentrations (30 mg/kg) are harmful. At least 3 parts per milligram should be included in the diet of rabbits in order to support healthy growth, according to reports.

Higher copper concentrations (100, 200, or 500 ppm) in the rabbit diet, however, might have a positive impact on growth rates, carcass dressing percentages, and feed conversion efficiency.

Humans typically do not experience chronic copper poisoning due to transport systems that control absorption and excretion.

These systems can be rendered inoperable by autosomal recessive mutations in copper transport proteins, which causes Wilson’s disease.

Which manifests as copper buildup and liver cirrhosis in individuals who have two faulty genes. Increased copper levels have also been connected to Alzheimer’s disease symptoms getting worse.

Human Exposure

The US’s time-weighted average (TWA) of 1 mg/m³ has been set as the permitted exposure limit (PEL) by the Occupational Safety and Health Administration (OSHA) for workplace exposure to copper dust and fumes.

The recommended exposure limit (REL), as established by the National Institute for Occupational Safety and Health (NIOSH), is 1 mg/m³, a time-weighted average.

The value of 100 mg/m³ is the IDLH (immediately threatening to life and health). Tobacco smoke has a copper component.

Heavy metals like copper that are easily absorbed by the tobacco plant and accumulate in its leaves come from the surrounding soil. They are easily absorbed by the body once the user inhales smoke. The effects on health are unclear.

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