The Story of Aluminum Experiment in 1827
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Laval University From the SelectedWorks of Fathi Habashi 2016 The tS ory of Aluminum Fathi Habashi Available at: https://works.bepress.com/fathi_habashi/189/ METALL-FOMETALL-RUBRSCHUNGRIK Berlin he repeated successfully Oersted’s The Story of Aluminum experiment in 1827. In 1836 he moved to Göttingen to accept a position at the Uni- versity and in 1845 succeeded in making Habashi, F. (1) aluminum in slightly larger amounts from which he was able to show that aluminum Aluminum was first produced on a commercial scale in France in 1856 by reduction was a light metal. of alumina with sodium. At the same time aluminum bronze was manufactured. Bauxite played an important role in the production of the metal. The French process Aluminum production in France gave way to the electrolytic process invented in 1888. Aluminum became the chief competitor for copper regarding its use in the electrical industry. In the beginning it French chemists were also active in research was more expensive than copper but since the 1960s it became much cheaper. Its to produce aluminum. Henri Sainte-Claire position in the Periodic Table is also discussed. Deville (1818-1881) (Fig. 4) professor of chemistry at the École Normale in Paris produced aluminum in 1854 by electro- aturally-occurring alum used sium and few days later, sodium using this lyzing molten aluminum chloride-sodium by alchemists to enhance the battery. Once these two reactive metals chloride mixture since the mixture has a dyeing of textile was known were available they became the focus of low-melting eutectic of 107 °C. However, to yield a white “earth” when intensive study. Their vigorous reaction this route was abandoned because, at that Nheated at high temperature. This white with water and their spontaneous burn- time, electric current needed for electroly- earth was known as alumina and was an ing in air was impressive. In 1808, Davy sis was obtained only from batteries, which exceptionally stable material that it was announced further his belief that the plen- were tedious to construct, to operate, and considered a chemical element like gold, tiful compound alumina was the earth to maintain. He, therefore, considered the copper, and tin. When Alessandro Volta (oxide) of an undiscovered metal. Since chemical method devised by Wöhler. In then, scientists had been making efforts to 1854 he was able to prepare a small bar obtain this new metal. of the metal he prepared at the Javel plant near Paris to show at the meeting of the A visitor to Copenhagen French Academy of Sciences. He replaced potassium by sodium because he thought Davy never made any aluminum himself, but in the early 1820s the Danish scientist Hans Christian Oersted (1777-1851) (Fig. 2) succeeded in producing a tiny sample of the metal in the laboratory by reducing the aluminum chloride with potassium amal- gam. He had prepared aluminum chloride few years earlier for the first time by heat- Fig. 1: Humphry Davy (1778-1829) ing a mixture of alumina and charcoal in a stream of chlorine. Chlorine at that time in northern Italy discovered in 1800 that an electric current was generated when two metals were separated by an electrolyte, chemists in Europe immediately started to Fig. 4: Henri Sainte-Claire Deville (1818- study this new phenomenon and tried to 1881) make use of it. Napoleon Bonaparte as First Consul invited Volta to Paris in 1801 to that sodium was easier to prepare by reduc- demonstrate to him at the French National tion of the carbonate with coal at high Institute (the body that replaced the French temperature since there was no explosions Academy during the revolutionary period), Fig. 2 and 3: Hans Christian Oersted (1777- associated with the reaction as the case the principle of his discovery. Napoleon 1851) and Friedrich Wöhler (1800-1882) with potassium. This change resulted in a was impressed by the demonstration. He major improvement because he discovered gave Volta the Gold Medal of the Institute was a laboratory curiosity isolated few that the reaction product sodium chloride and ordered funds to the École Polytech- years earlier by Carl Wilhelm Scheele. formed a readily fusible double salt with nique to build a large battery for research. Friedrich Wöhler (1800- 1882) (Fig. 3) on excess aluminum chloride that acted as a The news of Volta’s discovery reached Eng- his return from Stockholm after finishing protective layer allowing the globules of land rapidly and a very large battery simi- his studies there with Jöns Jacob Berzelius, aluminum to coalesce forming large lumps lar to the one constructed in Paris was built stopped in Copenhagen in 1824 to visit of the metal which was not the case with at the newly founded Royal Institution in the University. He met Oersted there and previous method. London where Humphry Davy (1778-1829) learned about his experiments to iso- The great French chemist Jean-Baptiste (Fig. 1) succeeded in 1807 to isolate potas- late aluminum. Now in his laboratory in Dumas (1800-1884), a friend of Sainte- METALL | 65.70. Jahrgang | 6/20119/2016 343 METALL-RUBMETALL-FORSCHUNGRIK Claire Deville, got an audience with entists had been making efforts to obtain lite deposits there. He discovered that the emperor Napoleon III and convinced this new metal. A Danish whaler brought deposit was of limited size and rightly con- him to subsidize the researches on alumi- a piece of the mineral cryolite, Na3AIF6, sidered that the French bauxite would be a num. Sainte-Claire Deville was also able found at Ivigtut, in south Greenland to more suitable raw material for an expand- to expose the bar at the Paris Exposition Copenhagen. In 1854, a process for the ing aluminum industry. in 1855 under the title The Silver of Clay recovery of alumina from cryolite was which was a great success. Sainte-Claire developed by Julius Thomsen (1826-1909) Deville was interested more in the scien- (Fig. 5) professor at the Technical Univer- tific aspects of the extraction of the metal sity of Copenhagen. The process involved than its commercial production. He there- heating the cryolite with limestone fol- fore suggested to his friend Paul Morin, a lowed by water leaching to extract sodium mining engineer, to undertake the indus- aluminate formed, leaving behind CaF2 trialization of the project. in the residue. Aluminum hydroxide was then precipitated from the aluminate solu- Alumina from alum Fig. 7 and 8: John Percy (1817–1889) and tion by CO2 leaving sodium carbonate in solution to be recovered as a by-product Heinrich Rose (1795-1864) In 1856, Morin built a plant to produce and (Fig. 6). market the new metal at Glacière district in By the early 1860’s a large-scale soda and The aluminum ore known as bauxite Paris. He first obtained alumina by decom- alumina production based on cryolite was was discovered in 1821 by Pierre Berthier position of alum a hydrated aluminum sul- in operation and was one of the largest (1782-1861) (Fig. 9) professor at the School fate, but the inhabitants in the neighbor- industries in Denmark. The process was of Mines in Paris, while prospecting for hood protested the emissions of SO2 from also transferred to few nearby countries iron ores in southern France. He called the plant. He had to move to Nanterre out- as well as in USA at the Pennsylvania Salt it “Terre d’alumine des Beaux” after the side Paris. Sainte-Claire Deville was also Company at Natrona near Pittsburgh. village of Les Beaux near Marseille where looking for a substitute for alum. However, in 1894 soda production from he made his discovery. The red color of cryolite ceased in Copenhagen because of the deposit had attracted his interest as Alumina from cryolite competition with the new Solvay process. a possible iron ore for the blast furnace In 1897 about 13,000 tons of the mineral in the district. However, it was found to Since Davy’s announcement that alumina were mined, the major part of which was contain too much Al2O3 to be of value for was the earth of an undiscovered metal sci- delivered to the Pennsylvania Company, this purpose. The name was changed later but three years later, the process was also to beauxite and then to bauxite. Bauxite abandoned in USA. Thomsen is best known was shown by thermal analysis to contain for developing the principle that the heat of a mixture of the hydroxides Al(OH)3 and formation is a measure of chemical affin- AlOOH and became the main raw material ity and for a four-volume work Thermo- for the modern aluminum industry. chemische Untersuchungen he published between 1882 and 1886. Aluminum from cryolite At the same time Sainte-Claire Deville was planning to produce aluminum on large Fig. 5: Julius Thomsen (1826-1909) scale by the reduction of alumina with sodium there were many attempts made to recover aluminum from cryolite. John Per- cy (1817–1889) (Fig. 7) at the Royal School of Mines in London in 1855 and simultane- Fig. 9 and 10: Pierre Berthier (1782-1861) ously Heinrich Rose in Berlin (1795-1864) and Louis Le Chatelier (1815-1873) (Fig. 8) reduced the mineral with sodium: Thermal method of treatment Na3AlF6 + 3Na → Al + 6NaF When the need arose to produce alumina, The process was used for a short time but methods were developed to treat bauxite. was abandoned because of the attack of Aluminum can be solubilized readily from silica lining of furnaces by the fluorides. bauxite by acids but on adding an alkali to the solution a gelatinous basic salt, rather Alumina from bauxite than a crystalline hydroxide is precipitat- ed.