61-604: Kolwezi or Kolwesi is the capital city of Lualaba Province in the south of the Democratic Republic of the Congo , west of Likasi . It has an airport and a railway to Lubumbashi . Just outside of Kolwezi there is the static inverter plant of the HVDC Inga-Shaba . The population is approximately 573,000. Before the creation of Lualaba province in 2015 Kolwezi had two territories attached to it and
122-413: A gnome (mine spirit) by others. Cobalt is a ferromagnetic metal with a specific gravity of 8.9. The Curie temperature is 1,115 °C (2,039 °F) and the magnetic moment is 1.6–1.7 Bohr magnetons per atom . Cobalt has a relative permeability two-thirds that of iron . Metallic cobalt occurs as two crystallographic structures : hcp and fcc . The ideal transition temperature between
183-589: A bucket used in mining, frequently mentioned by Agricola, namely the kobel/köbel (Latinized as modulus ). Another theory given by the Etymologisches Wörterbuch derives the term from kōbathium or rather cobathia ( κωβάθια , "arsenic sulfide" ) which occurs as noxious fumes. An etymology from Slavonic kowalti was suggested by Emanuel Merck (1902). W. W. Skeat and J. Berendes construed κόβαλος as "parasite", i.e. as an ore parasitic to nickel , but this explanation
244-452: A distinctive blue tint to glass. The color was long thought to be due to the metal bismuth . Miners had long used the name kobold ore ( German for goblin ore ) for some of the blue pigment-producing minerals . They were so named because they were poor in known metals and gave off poisonous arsenic -containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), which
305-408: A late 18th century writer. Later, Grimms' dictionary (1868) noted the kobalt/kobelt ore was blamed on the mountain spirit ( Bergmännchen [ de ] ) which was also held responsible for "stealing the silver and putting out an ore that caused poor mining atmosphere ( Wetter ) and other health hazards". Grimms' dictionary entries equated the word "kobel" with "kobold", and listed it as
366-519: A mere variant diminutive , but the latter is defined in it as a household spirit . Whereas some of the more recent commentators prefer to characterize the ore's namesake kobelt (recté kobel ) as a gnome . The early 20th century Oxford English Dictionary (1st edition, 1908) had upheld Grimm's etymology. However, by around the same time in Germany, the alternate etymology not endorsed by Grimm ( kob/kof "house, chamber" + walt "power, ruler")
427-481: A monsoon-influenced humid subtropical climate ( Köppen climate classification Cwa ). The city has a dry-winter humid subtropical climate (Cwa, according to the Köppen climate classification), with warm rainy summers and pleasant, dry winters, with most rainfall occurring during summer and early autumn. Annual average rainfall is 45.8 inches. The city is crossed by Transafrican Highway 9 (TAH 9), which connects it to
488-483: A source of hydroelectric power and a reservoir of water for the mining activities. Kolwezi and its cobalt mining economy was profiled in the May 24, 2021 edition of The New Yorker by writer Nicolas Niarchos. The acute financial and environmental impacts on the city and its economy were highlighted in the article. The rapid growth of the cobalt mining industry has caused a recent surge in the city's population. Kolwezi has
549-449: A transition metal-alkyl complex that is notable for its resistance to β-hydrogen elimination , in accord with Bredt's rule . The cobalt(III) and cobalt(V) complexes [Li(THF) 4 ] [Co(1-norb) 4 ] and [Co(1-norb) 4 ] [BF 4 ] are also known. Co is the only stable cobalt isotope and the only isotope that exists naturally on Earth. Twenty-two radioisotopes have been characterized:
610-559: A wide variety of coordination complexes with ammonia and amines, which are called ammine complexes . Examples include [Co(NH 3 ) 6 ] , [Co(NH 3 ) 5 Cl] ( chloropentamminecobalt(III) ), and cis - and trans - [Co(NH 3 ) 4 Cl 2 ] . The corresponding ethylenediamine complexes are also well known. Analogues are known where the halides are replaced by nitrite , hydroxide , carbonate , etc. Alfred Werner worked extensively on these complexes in his Nobel-prize winning work. The robustness of these complexes
671-528: Is +2 (cobalt(II)). These salts form the pink-colored metal aquo complex [Co(H 2 O) 6 ] in water. Addition of chloride gives the intensely blue [CoCl 4 ] . In a borax bead flame test , cobalt shows deep blue in both oxidizing and reducing flames. Several oxides of cobalt are known. Green cobalt(II) oxide (CoO) has rocksalt structure. It is readily oxidized with water and oxygen to brown cobalt(III) hydroxide (Co(OH) 3 ). At temperatures of 600–700 °C, CoO oxidizes to
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#1732783402263732-501: Is a chemical element ; it has symbol Co and atomic number 27. As with nickel , cobalt is found in the Earth's crust only in a chemically combined form, save for small deposits found in alloys of natural meteoric iron . The free element , produced by reductive smelting , is a hard, lustrous, somewhat brittle, gray metal . Cobalt-based blue pigments ( cobalt blue ) have been used since antiquity for jewelry and paints, and to impart
793-424: Is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy gamma rays . Cobalt is also used in the petroleum industry as a catalyst when refining crude oil. This is to purge it of sulfur, which is very polluting when burned and causes acid rain. Cobalt is the active center of a group of coenzymes called cobalamins . Vitamin B 12 , the best-known example of
854-679: Is also a constituency of the National Assembly as well as of the Provincial Assembly of its province. Each city is led by a mayor (fr. maire ) and is further divided into communes with each commune led by a burgomaster (fr. bourgmestre ). Currently mayors, burgomasters, and their deputies are appointed by the government. Elections to bring about elected local government in provincial capitals are scheduled for December 2023—September 2024. All provincial capitals are, by organic law , cities and do not need to meet
915-430: Is demonstrated by the optical resolution of tris(ethylenediamine)cobalt(III) ( [Co(en) 3 ] ). Cobalt(II) forms a wide variety of complexes, but mainly with weakly basic ligands. The pink-colored cation hexaaquocobalt(II) [Co(H 2 O) 6 ] is found in several routine cobalt salts such as the nitrate and sulfate. Upon addition of excess chloride, solutions of the hexaaquo complex converts to
976-459: Is excluded. In mid-2018, just before the general election of that year , the government upheld the 2013 granting of city status to a large number of populated places, including 65 not listed above. It was further decided to make these cities operational in stages. Since then the following ones have had their first mayor appointed and take office without being National Assembly districts : Download coordinates as: Cobalt Cobalt
1037-561: Is faulted for its anachronism since nickel was not discovered until 1751. Cobalt compounds have been used for centuries to impart a rich blue color to glass , glazes , and ceramics . Cobalt has been detected in Egyptian sculpture, Persian jewelry from the third millennium BC, in the ruins of Pompeii , destroyed in 79 AD, and in China, dating from the Tang dynasty (618–907 AD) and
1098-511: Is located on the eastern edge of the city. Kolwezi has several medical clinics and hospitals along with dozens of primary and secondary schools. Is an upscale neighborhood located in the center of Kolwezi. The area is home to several foreign workers and a number of guest houses. Manika Stadium is located in the Dilala neighborhood. Kolwezi's Central Train Station is located on the eastern edge of
1159-460: Is much more sensitive to oxidation than ferrocene. Cobalt carbonyl ( Co 2 (CO) 8 ) is a catalyst in carbonylation and hydrosilylation reactions. Vitamin B 12 (see below ) is an organometallic compound found in nature and is the only vitamin that contains a metal atom. An example of an alkylcobalt complex in the otherwise uncommon +4 oxidation state of cobalt is the homoleptic complex tetrakis(1-norbornyl)cobalt(IV) (Co(1-norb) 4 ),
1220-541: Is not found on Earth's surface because of its tendency to react with oxygen in the atmosphere. Small amounts of cobalt compounds are found in most rocks, soils, plants, and animals. In the ocean cobalt typically reacts with chlorine. In nature, cobalt is frequently associated with nickel . Both are characteristic components of meteoric iron , though cobalt is much less abundant in iron meteorites than nickel. As with nickel, cobalt in meteoric iron alloys may have been well enough protected from oxygen and moisture to remain as
1281-459: Is obtained by reducing the cobalt by-products of nickel and copper mining and smelting . Since cobalt is generally produced as a by-product, the supply of cobalt depends to a great extent on the economic feasibility of copper and nickel mining in a given market. Demand for cobalt was projected to grow 6% in 2017. Primary cobalt deposits are rare, such as those occurring in hydrothermal deposits , associated with ultramafic rocks , typified by
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#17327834022631342-419: Is one of the few simple stable cobalt(III) compounds. Cobalt(III) fluoride, which is used in some fluorination reactions, reacts vigorously with water. The inventory of complexes is very large. Starting with higher oxidation states, complexes of Co(IV) and Co(V) are rare. Examples are found in caesium hexafluorocobaltate(IV) (Cs 2 CoF 6 ) and potassium percobaltate (K 3 CoO 4 ). Cobalt(III) forms
1403-534: Is reduced to metal by the aluminothermic reaction or reduction with carbon in a blast furnace . The United States Geological Survey estimates world reserves of cobalt at 7,100,000 metric tons. The Democratic Republic of the Congo (DRC) currently produces 63% of the world's cobalt. This market share may reach 73% by 2025 if planned expansions by mining producers like Glencore Plc take place as expected. Bloomberg New Energy Finance has estimated that by 2030, global demand for cobalt could be 47 times more than it
1464-515: The Congo in 1914, mining operations shifted again. When the Shaba conflict started in 1978, the copper mines of Katanga Province nearly stopped production. The impact on the world cobalt economy from this conflict was smaller than expected: cobalt is a rare metal, the pigment is highly toxic, and the industry had already established effective ways for recycling cobalt materials. In some cases, industry
1525-527: The French Foreign Legion , were sent in to drive out the rebels and rescue any hostages. The Belgian army also deployed a force of some 750 Paracommando Regiment paratroopers and moved out just over 1,800 Europeans to other cities in the region. 700 Africans, including 250 rebels, 170 European hostages and 6 paratroopers died. Kolwezi is set on an arid plain in the south of the Democratic Republic of Congo . Upon its establishment in 1937 by
1586-567: The Ming dynasty (1368–1644 AD). Cobalt has been used to color glass since the Bronze Age . The excavation of the Uluburun shipwreck yielded an ingot of blue glass, cast during the 14th century BC. Blue glass from Egypt was either colored with copper, iron, or cobalt. The oldest cobalt-colored glass is from the eighteenth dynasty of Egypt (1550–1292 BC). The source for the cobalt
1647-676: The monoxide CoO. The metal reacts with fluorine (F 2 ) at 520 K to give CoF 3 ; with chlorine (Cl 2 ), bromine (Br 2 ) and iodine (I 2 ), producing equivalent binary halides . It does not react with hydrogen gas ( H 2 ) or nitrogen gas ( N 2 ) even when heated, but it does react with boron , carbon , phosphorus , arsenic and sulfur. At ordinary temperatures, it reacts slowly with mineral acids , and very slowly with moist, but not dry, air. Common oxidation states of cobalt include +2 and +3, although compounds with oxidation states ranging from −3 to +5 are also known. A common oxidation state for simple compounds
1708-552: The Bou-Azzer district of Morocco . At such locations, cobalt ores are mined exclusively, albeit at a lower concentration, and thus require more downstream processing for cobalt extraction. Several methods exist to separate cobalt from copper and nickel, depending on the concentration of cobalt and the exact composition of the used ore. One method is froth flotation , in which surfactants bind to ore components, leading to an enrichment of cobalt ores. Subsequent roasting converts
1769-609: The Congo The cities of the Democratic Republic of the Congo are administrative divisions of provinces with the exception of Kinshasa which itself has the status of a province. Cities are further divided into communes . They are led by mayors except for Kinshasa which is led by a governor. The 25 provinces of DR Congo are divided into 33 cities (fr. villes , sing. ville ) and 145 territories (fr. territoires , sing. territoire ). Each provincial division
1830-485: The DRC alone accounted for more than 50%. Cobalt is primarily used in lithium-ion batteries , and in the manufacture of magnetic , wear-resistant and high-strength alloys . The compounds cobalt silicate and cobalt(II) aluminate (CoAl 2 O 4 , cobalt blue) give a distinctive deep blue color to glass , ceramics , inks , paints and varnishes . Cobalt occurs naturally as only one stable isotope , cobalt-59. Cobalt-60
1891-477: The Egyptians used is not known. The word cobalt is derived from the 16th century German " kobelt ", a type of ore, as aforementioned. The first attempts to smelt those ores for copper or silver failed, yielding simply powder (cobalt(II) oxide) instead. Because the primary ores of cobalt always contain arsenic, smelting the ore oxidized the arsenic into the highly toxic and volatile arsenic oxide , adding to
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1952-533: The US. High purity cobalt was highly sought after for its use in jet engines and gas turbines. An adequate supply of the ore was found in Idaho near Blackbird canyon . Calera Mining Company started production at the site. Cobalt demand has further accelerated in the 21st century as an essential constituent of materials used in rechargeable batteries, superalloys, and catalysts. It has been argued that cobalt will be one of
2013-466: The Union Minière du Haut-Katangahe, the company cleared the land of the acacias and miombo trees that once grew atop Kolwezi’s rich mineral deposits. They subsequently built a simple low-rise town across the area’s rolling hills, with wide streets and bungalows for Europeans, whose neighborhoods were segregated from the poorly built ones where Congolese workers lived. The N39 highway runs through
2074-407: The anhydrous dichloride is blue, the hydrate is red. The reduction potential for the reaction Co + e → Co is +1.92 V, beyond that for chlorine to chloride, +1.36 V. Consequently, cobalt(III) chloride would spontaneously reduce to cobalt(II) chloride and chlorine. Because the reduction potential for fluorine to fluoride is so high, +2.87 V, cobalt(III) fluoride
2135-527: The atmosphere, weathering occurs; the sulfide minerals oxidize and form pink erythrite ("cobalt glance": Co 3 (AsO 4 ) 2 ·8H 2 O ) and spherocobaltite (CoCO 3 ). Cobalt is also a constituent of tobacco smoke . The tobacco plant readily absorbs and accumulates heavy metals like cobalt from the surrounding soil in its leaves. These are subsequently inhaled during tobacco smoking . The main ores of cobalt are cobaltite , erythrite , glaucodot and skutterudite (see above), but most cobalt
2196-414: The black cobalt(II) sulfides , CoS 2 ( pyrite structure), Co 2 S 3 ( spinel structure ), and CoS ( nickel arsenide structure). Four dihalides of cobalt(II) are known: cobalt(II) fluoride (CoF 2 , pink), cobalt(II) chloride (CoCl 2 , blue), cobalt(II) bromide (CoBr 2 , green), cobalt(II) iodide (CoI 2 , blue-black). These halides exist in anhydrous and hydrated forms. Whereas
2257-428: The blue cobalt(II,III) oxide (Co 3 O 4 ), which has a spinel structure . Black cobalt(III) oxide (Co 2 O 3 ) is also known. Cobalt oxides are antiferromagnetic at low temperature : CoO ( Néel temperature 291 K) and Co 3 O 4 (Néel temperature: 40 K), which is analogous to magnetite (Fe 3 O 4 ), with a mixture of +2 and +3 oxidation states. The principal chalcogenides of cobalt are
2318-424: The center of town on a northwest-southeast axis. Large open pit cobalt mines are located to the west and north of the city center. Rond Point de L'Indépendance is the traditional center of the city with more formally laid out neighborhoods located to the west of the traffic circle. The center of the city contains administrative offices, dozens of guesthouses and hotels, banks and restaurants. Mutoshi Technical Institute
2379-459: The cities of Lubumbashi and Dilolo . The city of Kolwezi has one of the main railway stations in Congo, from where mineral loads and passengers board every day. The station receives trains from the Benguela railway . The Kolwezi Airport serves Kolwezi and the surrounding area. The airport is located about 6 km (4 mi) south of Kolwezi. Cities of the Democratic Republic of
2440-475: The cobalt ore may have got its name from "a type of mine spirit/demon" ( daemon metallicus ) while stating that this is "apparently" the kobold. Joseph William Mellor (1935) also stated that cobalt may derive from kobalos ( κόβαλος ), though other theories had been suggested. Several alternative etymologies that have been suggested, which may not involve a spirit (kobel or kobold) at all. Karl Müller-Fraureuth conjectured that kobelt derived from Kübel ,
2501-465: The deep blue CoCl 2− 4 , which is tetrahedral. Softer ligands like triphenylphosphine form complexes with Co(II) and Co(I), examples being bis- and tris(triphenylphosphine)cobalt(I) chloride, CoCl 2 (PPh 3 ) 2 and CoCl(PPh 3 ) 3 . These Co(I) and Co(II) complexes represent a link to the organometallic complexes described below. Cobaltocene is a structural analog to ferrocene , with cobalt in place of iron. Cobaltocene
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2562-448: The free (but alloyed) metal. Cobalt in compound form occurs in copper and nickel minerals. It is the major metallic component that combines with sulfur and arsenic in the sulfidic cobaltite (CoAsS), safflorite (CoAs 2 ), glaucodot ( (Co,Fe)AsS ), and skutterudite (CoAs 3 ) minerals. The mineral cattierite is similar to pyrite and occurs together with vaesite in the copper deposits of Katanga Province . When it reaches
2623-418: The hcp and fcc structures is 450 °C (842 °F), but in practice the energy difference between them is so small that random intergrowth of the two is common. Cobalt is a weakly reducing metal that is protected from oxidation by a passivating oxide film. It is attacked by halogens and sulfur . Heating in oxygen produces Co 3 O 4 which loses oxygen at 900 °C (1,650 °F) to give
2684-483: The lack of reliable and comparable population figures, electoral districts are allocated seats in proportion to their voter registration numbers. The number of seats allocated to a city in the National Assembly and the Provincial Assembly is one measure of its relative political importance nationally and within its province respectively. In 2018 cities accounted for 27% of the electorate, or 16% when Kinshasa
2745-443: The main objects of geopolitical competition in a world running on renewable energy and dependent on batteries, but this perspective has also been criticised for underestimating the power of economic incentives for expanded production. The stable form of cobalt is produced in supernovae through the r-process . It comprises 0.0029% of the Earth's crust . Except as recently delivered in meteoric iron, free cobalt (the native metal )
2806-586: The most stable, Co , has a half-life of 5.2714 years; Co has a half-life of 271.8 days; Co has a half-life of 77.27 days; and Co has a half-life of 70.86 days. All the other radioactive isotopes of cobalt have half-lives shorter than 18 hours, and in most cases shorter than 1 second. This element also has 4 meta states , all of which have half-lives shorter than 15 minutes. The isotopes of cobalt range in atomic weight from 50 u ( Co) to 73 u ( Co). The primary decay mode for isotopes with atomic mass unit values less than that of
2867-471: The neighborhood with train service to Likasi and Lubumbashi . Kolwezi is an important mining centre for copper and cobalt . There are also uranium , radium , oxide ores, and lime deposits. The Musonoi mine is a set of open-cut pits near Kolwezi from which copper and other metals have been extracted since the 1940s. The nearby Lake Nzilo was created by damming the Lualaba River to provide
2928-474: The notoriety of the ore. Paracelsus , Georgius Agricola , and Basil Valentine all referred to such silicates as "cobalt". Swedish chemist Georg Brandt (1694–1768) is credited with discovering cobalt c. 1735 , showing it to be a previously unknown element, distinct from bismuth and other traditional metals. Brandt called it a new "semi-metal", naming it for the mineral from which he had extracted it. He showed that compounds of cobalt metal were
2989-417: The only stable isotope, Co, is electron capture and the primary mode of decay in isotopes with atomic mass greater than 59 atomic mass units is beta decay . The primary decay products below Co are element 26 ( iron ) isotopes; above that the decay products are element 28 (nickel) isotopes. Many different stories about the origin of the word "cobalt" have been proposed. In one version the element cobalt
3050-430: The ores to cobalt sulfate , and the copper and the iron are oxidized to the oxide. Leaching with water extracts the sulfate together with the arsenates . The residues are further leached with sulfuric acid , yielding a solution of copper sulfate. Cobalt can also be leached from the slag of copper smelting. The products of the above-mentioned processes are transformed into the cobalt oxide (Co 3 O 4 ). This oxide
3111-638: The requirement of having a population of at least 100,000. The capital city of Kinshasa is a one of a kind administrative division due to article 2 of the Constitution which makes it a division of the country and gives it the status of a province. In practice this means that—like a province—it has a provincial government with an elected governor and an Assembly, but—like a city—it is divided into communes led by burgomasters. Uniquely, its 24 communes are also Provincial Assembly constituencies and are grouped into four National Assembly constituencies. Due to
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#17327834022633172-546: The source of the blue color in glass, which previously had been attributed to the bismuth found with cobalt. Cobalt became the first metal to be discovered since the pre-historical period. All previously known metals (iron, copper, silver, gold, zinc, mercury, tin, lead and bismuth) had no recorded discoverers. During the 19th century, a significant part of the world's production of cobalt blue (a pigment made with cobalt compounds and alumina) and smalt ( cobalt glass powdered for use for pigment purposes in ceramics and painting)
3233-408: The time was Georgius Agricola . He was also the oft-quoted authority on the mine spirits called " kobel " (Latinized as cobalus or pl. cobali ) in a separate work. Agricola did not make an connection between the similarly named ore and spirit. However, a causal connection (ore blamed on "kobel") was made by a contemporary, and a word origin connection (word "formed" from cobalus ) made by
3294-488: The time). In the 2015 repartitioning this was undone, the two territories and the city proper became separate parts of Lualaba province with the city as capital of the new province. On Saturday, 13 May 1978, ex- Katangese soldiers supported by Angola occupied the city. The government of Zaire asked Belgium , France, Morocco and the United States to restore order. The 2e REP , an elite paratroopers unit of
3355-448: The type, is an essential vitamin for all animals. Cobalt in inorganic form is also a micronutrient for bacteria , algae , and fungi . The name cobalt derives from a type of ore considered a nuisance by 16th century German silver miners, which in turn may have been named from a spirit or goblin held superstitiously responsible for it; this spirit is considered equitable to the kobold (a household spirit ) by some, or, categorized as
3416-646: The whole was known as the Kolwezi District . The settlement was created in 1938 to be the headquarters for the western mining group of the Union Minière du Haut Katanga . In 1971 it obtained city status and consisted of the communes of Dilala and Manika . In 1976 the territories of Lubudi and Mutshatsha , both previously part of Lualaba District , were attached to it to form the Kolwezi District (districts were called sub-regions at
3477-486: Was able to change to cobalt-free alternatives. In 1938, John Livingood and Glenn T. Seaborg discovered the radioisotope cobalt-60 . This isotope was famously used at Columbia University in the 1950s to establish parity violation in radioactive beta decay . After World War II, the US wanted to guarantee the supply of cobalt ore for military uses (as the Germans had been doing) and prospected for cobalt within
3538-557: Was being proposed as more convincing. Somewhat later, Paul Kretschmer (1928) explained that while this "house ruler" etymology was the proper one that backed the original meaning of kobold as household spirit, a corruption later occurred introducing the idea of "mine demon" to it. The present edition of the Etymologisches Wörterbuch (25th ed., 2012) under "kobold" lists the latter, not Grimm's etymology, but still persists, under its entry for "kobalt", that while
3599-776: Was carried out at the Norwegian Blaafarveværket . The first mines for the production of smalt in the 16th century were located in Norway, Sweden, Saxony and Hungary. With the discovery of cobalt ore in New Caledonia in 1864, the mining of cobalt in Europe declined. With the discovery of ore deposits in Ontario , Canada, in 1904 and the discovery of even larger deposits in the Katanga Province in
3660-443: Was named after " kobelt ", the name which 16th century German silver miners had given to a nuisance type of ore which occurred that was corrosive and issued poisonous gas. Although such ores had been used for blue pigmentation since antiquity, the Germans at that time did not have the technology to smelt the ore into metal (cf. § History below). The authority on such kobelt ore (Latinized as cobaltum or cadmia ) at
3721-499: Was ultimately named for the kobold . Today, some cobalt is produced specifically from one of a number of metallic-lustered ores, such as cobaltite (CoAsS). The element is more usually produced as a by-product of copper and nickel mining. The Copperbelt in the Democratic Republic of the Congo (DRC) and Zambia yields most of the global cobalt production. World production in 2016 was 116,000 tonnes (114,000 long tons; 128,000 short tons) (according to Natural Resources Canada ), and
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