User:R8R/History of aluminium



Aluminium is a comparably new element in human applications. Its source ore, alum, has been known since the 5th century BCE; it was extensively used by the ancients for dyeing and city defense; the former usage would only be more important in the medieval Europe. Scientists of the Renaissance figured alum was a salt of a new earth; during the Age of the Enlightenment, it was established that the earth was an oxide of a new metal. Discovery of this new metal was convincingly announced in 1825 by Danish physicist Hans Christian Ørsted; his work would be greatly extended on by German chemist Friedrich Wöhler.

Aluminium metal was very difficult to synthesize and thus very rare. After its discovery, its price exceeded that of gold; the rarity of aluminium would only be reduced after the first industrial production was initiated by French chemist Henri Etienne Sainte-Claire Deville in 1856. Aluminium became, however, much more available to the general public with the Hall–Héroult process developed by French engineer Paul Héroult and American engineer Charles Martin Hall in 1886 and the Bayer process developed by Austrian chemist Carl Joseph Bayer in 1889. These methods have been used for aluminium production up to the present day.

After these methods were applied for mass production of aluminium, the metal has been extensively used in industry and everyday lives. Aluminium has been used for aviation, architecture, and packaging among others. Its production grew exponentially in the 20th century and aluminium became an exchange commodity in the 1970s. The production was 6,800 metric tons in 1900; in 2013, it exceeded 50,000,000 tons.

Early history


The history of aluminium has been shaped by usage of alum. First written record of alum, made by Greek historian Herodotus, dates back to the 5th century BCE. The ancients are known to have used alum as dyeing mordants and as astringents for dressing wounds; in addition to that, alum was used in medicine, as a fire-resistant coating for wood, and in chemical milling. The aluminium metal was unknown to them. Roman historian Pliny the Elder recorded a story about a metal that was bright as silver but much lighter was presented to the Emperor Tiberius (reigned 14–37 CE), who had the discoverer killed in order to ensure the metal would not diminish the value of his gold and silver assets. Some sources suggest a possibility that this metal was aluminium; however, this claim has been disputed. It is possible that the Chinese were able to produce aluminium-containing alloys during the reign of the first Jin dynasty (265–420).

After the Crusades, alum was a subject of international commerce; it was indispensable in European fabric industry. Alum was imported to Europe from the eastern Mediterranean until the mid-15th century, when the Ottomans tremendously raised the export taxes. Some alum mines were worked in Catholic Europe, but they could only provide little alum. Thus, when Giovanni da Castro, godson of the Pope Pius II, discovered in 1460 a rich source of alum at Tolfa near Rome, he reported excitedly to his godfather, "today I bring you victory over the Turk".

Establishing nature of alum


The nature of alum remained unknown. Around 1530, Swiss physician Paracelsus identified alum as separate from vitriole (sulfates), suggesting it was a salt of an earth of alum. In 1595, German doctor and chemist Andreas Libavius demonstrated that alum and green and blue vitriole were formed by the same acid but different earths; for the undiscovered earth that formed alum, he proposed the name "alumina". In 1702, German chemist Georg Ernst Stahl clearly stated his belief that the unknown base of alum was of the nature of lime or chalk; this mistake was shared by many scientists for another half a century. In 1722, German chemist Friedrich Hoffmann announced his belief that alum was a distinct earth. In 1728, French chemist Étienne Geoffroy Saint-Hilaire suggested that alum was formed by an unknown earth and the sulfuric acid; however, he mistakenly believed that burning of that earth yielded silica. In 1739, French chemist Jean Gello proved the equivalence between the earth in clay and the earth resulting from reaction of alkali on alum. In 1746, German chemist Johann Heinrich Pott showed that the precipitate obtained when an alkali is poured into a solution of alum is quite different from lime and chalk.

In 1754, German chemist Andreas Sigismund Marggraf synthesized the earth of alum by boiling clay in sulfuric acid and subsequently adding potash. He realized that the earth of alum results from adding soda, potash, or alkali to a solution of alum. He described the earth as alkaline for he discovered it can dissolve in acids when dried. Marggraf also described salts of the earth of alum: the chloride, the nitrate, and the acetate. In 1758, French chemist Pierre Macquer wrote that alumina resembled a metallic earth. In 1767, Swedish chemist Torbern Bergman published an article describing crystallization of alum from a solution obtained from boiling alunite in sulfuric acid followed by addition of potash. He also synthesized alum as a reaction product between sulfates of aluminium and potassium, thereby demonstrating that alum was a double salt. In 1776, German pharmaceutical chemist Carl Wilhelm Scheele demonstrated that both alum and silica originate from clay and that alum does not contain silicon. Geoffroy's mistake was only corrected by German chemist and pharmacist Johann Christian Wiegleb who determined in 1785 that contrary to contemporary belief, the earth of alum could not be synthesized from slilca and alkalies.

In 1782, French chemist Antoine Lavoisier wrote he considered highly probable that alumina was an oxide of a metal which had an affinity for oxygen so strong no known reducing agents could overcome it. In 1783, Lavoisier replaced the dominant phlogiston theory with the idea of oxygen combustion and stated that metallic earths were oxides of their metals. Swedish chemist Jöns Jacob Berzelius suggested in 1815 the formula AlO3 for alumina. The correct formula, Al2O3, was established by the German chemist Eilhard Mitscherlich in 1821; this helped Berzelius determine the correct atomic weight of the metal, 27.

Synthesis of metal
In 1760, French chemist Theodor Baron de Henouville declared he believed alumina was a metallic earth and first attempted to reduce it to its metal, at which he was unsuccessful. His means to attempt the reduction were not reported but he claimed he had tried every method of reduction known at the time. It is probable that he mixed alum with carbon or some organic substance, with salt or soda for flux, and heated as highly as possible in a charcoal fire.

In 1790, Austrian chemists Anton Leopold Ruprecht and Matteo Tondi repeated Baron's experiments, significantly increasing the temperatures; they found small metallic particles, which they believed to be the sought-after metal, but later experiments by other chemists showed these were only iron phosphide from impurities in charcoal and bone ash. German chemist Martin Heinrich Klaproth commented in an aftermath, "if there exists an earth which has been put in conditions where its metallic nature should be disclosed, if it had such, an earth exposed to experiments suitable for reducing it, tested in the hottest fires by all sorts of methods, on a large as well as on a small scale, that earth is certainly alumina, yet no one has yet perceived its metallization." Later, Lavoisier in 1794 and French chemist Louis-Bernard Guyton de Morveau in 1795 melted alumina to a white enamel in a charcoal fire fed by pure oxygen but found no metal. American chemist Robert Hare in 1802 melted alumina with an oxyhydrogen blowpipe, also obtaining the enamel, but still found no metal.



In 1807, British chemist Humphry Davy attempted to electrolyze alumina with alkaline batteries; in fact, he did electrolyze it, but the metal formed contained alkali metals potassium and sodium and Davy had no means to separate the desired metal from these two. He then tried to heat alumina with potassium metal; some potassium oxide indeed was formed, but he was unable to find the sought-after metal. In 1808, Davy set up a different experiment on electrolysis of alumina; he did experimentally establish that alumina was subject to decomposition in the electric arc, but he was unable to separate the metal from iron, with which it alloyed. Finally Davy tried yet another electrolysis experiment, seeking to collect the metal on iron, but was again unable to separate the two. During his experiments, Davy suggested the metal be named alumium in 1808 and aluminum in 1812, thus producing the modern name.

In 1813, American chemist Benjamin Silliman repeated Hare's experiment and while he did at one moment obtain small granules of the sought-after metal, it almost immediately burned.

Production of the metal was first claimed in 1824 by Danish physicist and chemist Hans Christian Ørsted. He reacted anhydrous aluminium chloride with potassium amalgam, yielding a lump of metal looking similar to tin. He presented his results and demonstrated a sample of the new metal in 1825. In 1826, he wrote that "aluminium has a metallic luster and somewhat grayish color and breaks down water very slowly"; this hints that he had obtained an aluminium–potassium alloy rather than pure aluminium. Ørsted himself was not convinced that he had obtained aluminium and gave little importance to his discovery; a different source suggests he could not continue his research because of financial reasons. Because of this and that he published his work in an unknown to the general European public Danish magazine, he is often not credited as the discoverer of the element.

Berzelius attempted isolation of the metal in 1825; he carefully washed in a crucible the potassium analog of the base salt in cryolite; he had correctly identified the formula of this salt prior to the experiment as K3AlF6. He found no metal; however, his experiment came very close to succeeding and was successfully reproduced many times later. Berzelius's mistake was in using an excess of potassium, which made the solution too alkaline and thus dissolved all newly formed aluminium.

German chemist Friedrich Wöhler visited Ørsted in 1827. Ørsted told Wöhler he did not intend to continue his research on aluminium extraction. Wöhler was engaged with the problem and investigated it on his return from Denmark. After repeating Ørsted's experiments, Wöhler did not identify any aluminium. (The reason for this inconsistency was only discovered in 1921.) He conducted a similar experiment in 1827 by mixing anhydrous aluminium chloride with potassium and produced a powder of aluminium. In 1845, he was able to produce small pieces of the metal and described some physical properties of this metal. Wöhler's description of properties of aluminium also indicates that he obtained impure aluminium.

Rare metal
As Wöhler's method could not yield great quantities of aluminium, the metal remained rare; its cost exceeded that of gold.



French chemist Henri Etienne Sainte-Claire Deville announced an industrial method of aluminium production in 1854 at the Paris Academy of Sciences. Aluminium trichloride could be reduced by sodium, which was more convenient and less expensive than potassium, which Wöhler had used. Subsequently, bars of aluminium were exhibited for the first time to the general public at the Exposition Universelle of 1855. The metal was presented there as "the silver from clay", and this name was soon widely used. Napoleon III of France subsidied Deville's research, which cost in total about 20 annual outcomes of an ordinary family. Prior to the exposition, Napoleon is reputed to have held a banquet where the most honored guests were given aluminium utensils, while the others made do with gold. In 1856, Deville, the Moran brothers, and the Rousseau brothers established the world's first industrial production of aluminium at the Tissier brothers' smelter in Rouen. From 1855 to 1859, the price of aluminium dropped by an order of magnitude, from US$500 to $40 per pound. Even then, aluminium was still not of great purity and produced aluminium differed in properties by sample.

Deville's smelter moved in 1856–1857 to La Glacière, Nanterre, and finally to Salindres. The smelter was soon acquired by the French company Pechiney and the Compagnie d’Alais et de la Camargue, which later became world's largest in chemical aluminium production. The technology at the factory continued to improve, and the output in Salindres in 1872 exceeded that in Nanterre in 1857 by 900 times. The factory in Salindres used bauxite as the primary aluminium ore; some chemists, including Deville, sought to employ cryolite, but none surpassed the existing techniques. British engineer William Gerhard set up a plant employing cryolite as the primary raw material in Battersea, London, in 1856, but technical and financial difficulties forced closure of the plant in three years.

Some other chemists also sought to industrialize the production of aluminium. British ironmaster Isaac Lowthian Bell started to produce aluminium in 1860 and continued his production until 1874. During the opening of his factory, he waved the crowd with a unique and costly aluminium top hat. British engineer James Fern Webster launched industrial production of aluminium by reduction with sodium in 1882; his aluminium was much purer than Deville's. A number of other productions was set up in the 1880s. However, all were obsoleted with the electrolytic production of aluminium.

At the next fair in Paris in 1867, the visitors were presented aluminium wire and foil; by the time of the next fair in 1878, aluminium had become a symbol of the future.

Electrolytic production


Aluminium was first synthesized electrolytically in 1854 by Deville and German chemist Robert Wilhelm Bunsen. Their electrolysis methods did not become the basis for industrial production of aluminium because electrical supplies were inefficient at the moment; this would only change with the invention of the dynamo by Belgian engineer Zénobe-Théophile Gramme in 1870 and the three-phase current by Russian engineer Mikhail Dolivo-Dobrovolsky in 1889.

The first industrial large-scale production method was independently developed by French engineer Paul Héroult and American engineer Charles Martin Hall; it is now known as the Hall–Héroult process. Héroult long could not find enough interest in his invention as demand for aluminium was still small; the factory in Salindres did not wish to improve the process they employed. Heroult with his companions founded Aluminium Industrie Aktien Gesellschaft in 1888. That year, they started industrial production of aluminium bronze in Neuhausen am Rheinfall in 1888. This production was only active for a year; but during that time, Société électrométallurgique française was founded in Paris. The society purchased Héroult's patents and appointed him to the position of director of a smelter in Isère, which would produce on a large scale aluminium bronze at the initiation and pure aluminium in a few months.



At the same time, Hall invented the same process and successfully tested it; he then sought to employ it for a large-scale production; for that, however, the existing smelter would have to radically change their production methods, which they were not willing to do in part because a mass production aluminium would then immediately drop the price of the metal. He started the Pittsburgh Reduction Company in 1888 where he initiated mass production of aluminium. In the coming years, this technology was improved on and new factories were constructed.

The Hall–Héroult process converts alumina into the metal; Austrian chemist Carl Joseph Bayer discovered a way of purifying bauxite to yield alumina in 1889, now known as the Bayer process. Modern production of the aluminium metal is based around the Bayer and Hall–Héroult processes. The Hall–Héroult process was further improved in 1920 by a team led by Swedish chemist Carl Wilhelm Söderberg; this improvement greatly increased the world output of aluminium.

Mass usage
"Give me 30,000 tonnes of aluminium, and I will win the war."



Prices of aluminium did drop and aluminium had become widely used in jewelry, everyday items, eyeglass frames, and optical instruments, to name just a few, by the early 1890s. Aluminium tableware began to be produced in the late 19th century and gradually supplanted copper and cast iron tableware in the first decades of the 20th century. Aluminium foil was also popularized at that time. Aluminium is soft and light; it was soon discovered, however, that alloying it with other metals could increase its hardness while preserving the low density. Aluminium's ability to form alloys with other metals provided the metal many uses in the late 19th and early 20th centuries. For instance, aluminium bronze is applied to make flexible bands, sheets, and wire and is widely employed in the shipbuilding and aviation industries. During the World War I, major governments demanded large shipments of aluminium for light strong airframes. They often subsidized factories and the necessary electrical supply systems. Aviation during that time employed a new aluminium alloy, duralumin, invented in 1903 by German materials scientist Alfred Wilm. Likewise, the civil airplane industry has used aluminium for airframes as well. Aluminium recycling started in the early 1900s and has been extensive since as aluminium is not impaired by recycling and thus can be recycled repeatedly. Overall production of aluminium peaked during the war: while the world production of aluminium in 1900 was 6,800 metric tons, the annual production first exceeded 100,000 metric tons in 1916. This peak would be followed by a decline, later again changed to a swift growth.

During the first half of the 20th century, normalized price for aluminium continuously fell from $14,000 in 1900 to $2,340 in 1948 (in 1998 United States dollars), with some exceptions such as the sharp price rise during the World War I. By the mid-20th century, aluminium had become a part of everyday lives, also becoming an essential component of houseware. Aluminium freight cars first appeared in 1931. Their lighter weight allowed them to carry more cargo. Aluminium's corrosion resistance established it as a construction material for boats during the 1930s; they received wide recognition in the early 1950s. During the 1930s, aluminium emerged as a civil engineering material, with buildings using for both basic construction and interior, and advanced its use in military engineering, for both airplanes and land armor vehicle engines. During World War II, the production peaked again: world production for the first time exceeded 1,000,000 tons in 1941. The United Kingdom, for instance, started an ambitious program of aluminium recycling; the Minister of Aircraft Production issued an appeal to the common people to donate any household aluminium for airplane building. The Soviet Union received nearly 328,000 metric tons of aluminium with the Lend-Lease policy; this aluminium would be used in aircraft and tank engines. Without these shipments, efficiency of the Soviet aircraft industry would have fallen by over a half. The production would again fall after the intensification caused by the war but then would rise again.

Exchange commodity


In the beginning of the second half of that century, the space race began. Earth's first artificial satellite, launched in 1957, consisted of two separate aluminium semi-spheres joined together and all subsequent space vehicles have been made of aluminium. The aluminium can was invented in 1956 and employed as a storage for drinks in 1958. In the 1960s, aluminium was employed for production of wires and cables. High-speed trains that appeared in the 1970s commonly use aluminium for its low weight. For the same reason, aluminium content in cars is growing.

By 1955, the market had been mostly divided by the Six Majors: Alcoa (successor of Hall's Pittsburgh Reduction Company), Alcan (originated as a part of that company), Reynolds (specialized in foil production), Kaiser, Pechiney (successor of Pechiney and the Compagnie d’Alais et de la Camargue that bought the smelter from Deville), and Alusuisse (successor of Heroult's Aluminium Industrie Aktien Gesellschaft), with their summary share of the market equaling 86%. From 1945, aluminium consumption grew by almost 10% each year, gaining ground in building applications, electric cables, basic foils, and the aircraft industry. In the early 1970s, an additional boost came from the development of aluminium beverage cans. Real prices continued to decline until this time as extraction and processing costs were lowered over technological progress and the increased production of aluminium, which first exceeded 10,000,000 tons in 1971.



By 1975, aluminium's main uses had been in construction, consumer durables, containers and packaging, electrical engineering materials, machinery and equipment, and transportation; these same uses have remained main ever since. In the 1970s, the increased demand for aluminium made it an exchange commodity; it entered the London Metal Exchange, the oldest industrial metal exchange in the world, in 1978. After aluminium became an exchange commodity, aluminium has been traded for United States dollars and its price fluctuated along with the exchange rates of the currency. The need to exploit lower-grade poorer quality deposits and the use of fast increasing input costs (above all, energy) increased the net cost of aluminium; real prices began to grow in the 1970s with the rise of energy cost.

This along with the change of tariffs and taxes started redistribution of the shares of world producers: while the United States, the Soviet Union, and Japan accounted for nearly 60% of the world's primary production in 1972 (and their combined shares of consumption of primary aluminium were also close to 60%), their composite share only slightly exceeded 10% in 2012. Production moved from the United States, Japan, and Western Europe to Australia, Canada, the Middle East, Russia, and China, where production was cheaper. Production costs in the late 20th century changed because of advances in technology, lower energy prices, exchange rates of the US dollar, and alumina prices. The BRIC countries' combined shares greatly grew in the first decade of the 21st century, from 32.6% to 56.5% in primary production and 21.4% to 47.8% in primary consumption. China is accumulating an especially large share of world's production thanks to thanks to abundance of resources, cheap energy, and governmental stimuli; it also increased its consumption share from 2% in 1972 to 40% in 2010. The only other country with a two-digit percentage was the United States with 11%; no other country exceeded 5%.

The world output continued to grow: the annual production of aluminium exceeded 50,000,000 metric tons in 2013. In 2015, it was record 57,500,000 tons.