- Key People:
- Anders Gustav Ekeberg
tantalum
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What is tantalum?
Tantalum (Ta) is a bright, silver-gray chemical element with atomic number 73. It is a very hard metal that belongs to Group 5 (Vb) of the periodic table. Tantalum resists most acids at normal temperatures, with the exception of hydrofluoric acid. The Swedish chemist Anders Gustaf Ekeberg discovered tantalum in 1802 and named it after the mythological figure Tantalus.
Tantalum is relatively rare and has about the same abundance as uranium. It is commonly found with niobium in minerals like columbite-tantalite. Tantalum is mainly used in corrosion-resistant chemical equipment and electrolytic capacitors. Tantalum carbide (TaC) is a very high-melting heavy dark yellow or brown crystalline compound that is one of the hardest substances known.
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What does tantalum look like?
Tantalum (Ta) is a bright, silver-gray metal with high density, extreme melting point, and excellent acid resistance. It's a very hard metal. Tantalum is closely associated with niobium in ores and properties. Tantalum is found in the columbite-tantalite and pyrochlore-microlite series of minerals. Tantalum carbide (TaC) is a dark yellow or brown crystalline compound.
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Where is tantalum found in nature?
Tantalum, closely associated with niobium, is a relatively rare element found in minerals like columbite-tantalite and pyrochlore-microlite series. Tantalum can also be located, along with niobium, in columbite [(Fe, Mn)(Nb, Ta)2O6].
Significant columbite deposits exist in Nigeria and Congo (Kinshasa), often as a byproduct of tin mining. Pyrochlore mines, another source of tantalum, are found in Minas Gerais and Goi\u00e1s, Brazil, and Saint Honor\u00e9, Quebec, Canada. Additionally, native tantalum metal, containing some niobium, can be sparingly found in placers in Russia's Ural and possibly Altai Mountains. Rwanda is the world’s largest extractor of tantalum.
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What are the main uses of tantalum?
Tantalum is a silver-gray metal with a high melting point and resistance to acids. Its main applications are in:
- Electrolytic capacitors Due to their high capacitance per volume, tantalum capacitors are common in small electronic circuits.
- Chemical equipment Tantalum's corrosion resistance makes it useful in chemical processing.
- Medical implants Tantalum is used in prosthetic devices and for repairing hernias and other body defects.
- Cutting tools Tantalum carbide (TaC) is an extremely hard compound used in tools for machining hard metals.
- Electronics Tantalum is used as getters and components in electron tubes and rectifiers.
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Why is tantalum important in making electronic devices?
Tantalum is a bright, silver-gray metal with a high density, an extremely high melting point, and excellent resistance to acids. Tantalum is important in making electronic devices because it is used in electrolytic capacitors. Tantalum capacitors have the highest capacitance per unit volume of any capacitors and are used extensively in miniaturized electrical circuitry. It is also used in electron tubes and rectifiers.
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How is tantalum extracted and purified for industrial use?
Tantalum is extracted from ores like columbite-tantalite and pyrochlore-microlite. The process begins with solvent extraction to separate tantalum from niobium compounds.
Here's a summary:
1. The tantalum-rich ore is crushed, ground, and decomposed in hydrofluoric acid.
2. A liquid-liquid extraction process follows, where tantalum and niobium dissolve in a slightly acidic aqueous solution. An organic solvent is mixed in, extracting the tantalum as a fluoride into the organic solution, while niobium remains in the aqueous residue.
3. Tantalum is then reduced to metallic tantalum powder, and massive metal is produced using powder metallurgy techniques.
4. Electrolysis of fused salts or reduction of fluoro complexes with a reactive metal like sodium can also yield tantalum.4 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.
tantalum (Ta), chemical element, bright, very hard, silver-gray metal of Group 5 (Vb) of the periodic table, characterized by its high density, extremely high melting point, and excellent resistance to all acids except hydrofluoric at ordinary temperatures.
Closely associated with niobium in ores and in properties, tantalum was discovered (1802) by the Swedish chemist Anders Gustaf Ekeberg and named after the mythological character Tantalus because of the tantalizing problem of dissolving the oxide in acids. Due to the great chemical similarity of niobium and tantalum, the establishment of the individual identities of the two elements was very difficult. Tantalum was soon identified with niobium (then called columbium), but in 1844 the German chemist Heinrich Rose demonstrated their distinct characters. Although some of the impure metal was isolated earlier, the Russian chemist Werner Bolton prepared (1903) the first ductile tantalum, which was used briefly as incandescent lamp-filament material.
Relatively rare, tantalum is about as abundant as uranium. It occurs, with niobium, in the columbite–tantalite series (in which columbite [FeNb2O6] and tantalite [FeTa2O6] occur in highly variable ratios) and the pyrochlore–microlite series of minerals. Native tantalum metal with some niobium and traces of manganese and gold occurs sparingly in Russia in placers in the Ural Mountains and possibly the Altai Mountains in Central Asia. Rwanda is the world’s largest extractor of tantalum. (For mineralogical properties, see native element [table].)
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Tantalum is separated from niobium compounds by solvent extraction in a liquid-liquid process and is then reduced to metallic tantalum powder. The massive metal is produced by powder metallurgy techniques. It can also be obtained by either electrolysis of fused salts or reduction of fluoro complexes with a very reactive metal such as sodium. The most important uses for tantalum are in electrolytic capacitors and corrosion-resistant chemical equipment. Tantalum capacitors have the highest capacitance per unit volume of any capacitors and are used extensively in miniaturized electrical circuitry. Other uses include getters and components in electron tubes, rectifiers, and prosthetic devices.
Tantalum is chemically much like niobium because both have similar electronic configurations and because the radius of the tantalum ion is nearly the same as that of niobium as a result of the lanthanoid contraction. Tantalum is usually in the +5 oxidation state in its compounds; lower oxidation states, especially from +2 to +4, have been prepared. Tantalum compounds are relatively unimportant commercially, although the carbide TaC is used in cemented-carbide tools for machining hard metals. Nearly all naturally occurring tantalum is in one stable isotope, tantalum-181. However, a small amount, 0.012 percent, is tantalum-180, which has the unusual property of being found in its excited state. The tantalum-180 excited state has a half-life of more than 1.2 × 1015 years; the ground state (the lowest energy state) has a half-life of only 8.154 hours.
| atomic number | 73 |
|---|---|
| atomic weight | 180.94788 |
| melting point | 2,996 °C (5,425 °F) |
| boiling point | 5,425 °C (9,797 °F) |
| specific gravity | 16.6 at 20 °C (68 °F) |
| oxidation states | +2, +3, +4, +5 |
| electron configuration | [Xe]4f 145d36s2 |