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Vanadium

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Vanadium, 23V
Vanadium
Pronunciation/vəˈndiəm/ (və-NAY-dee-əm)
Appearanceblue-silver-grey metal
Standard atomic weight Ar°(V)
Vanadium in the periodic table
Hydrogen Helium
Lithium Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon
Sodium Magnesium Aluminium Silicon Phosphorus Sulfur Chlorine Argon
Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine Krypton
Rubidium Strontium Yttrium Zirconium Niobium Molybdenum Technetium Ruthenium Rhodium Palladium Silver Cadmium Indium Tin Antimony Tellurium Iodine Xenon
Caesium Barium Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium Ytterbium Lutetium Hafnium Tantalum Tungsten Rhenium Osmium Iridium Platinum Gold Mercury (element) Thallium Lead Bismuth Polonium Astatine Radon
Francium Radium Actinium Thorium Protactinium Uranium Neptunium Plutonium Americium Curium Berkelium Californium Einsteinium Fermium Mendelevium Nobelium Lawrencium Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Nihonium Flerovium Moscovium Livermorium Tennessine Oganesson


V

Nb
titaniumvanadiumchromium
Atomic number (Z)23
Groupgroup 5
Periodperiod 4
Block  d-block
Electron configuration[Ar] 3d3 4s2
Electrons per shell2, 8, 11, 2
Physical properties
Phase at STPsolid
Melting point2183 K ​(1910 °C, ​3470 °F)
Boiling point3680 K ​(3407 °C, ​6165 °F)
Density (at 20° C)6.099 g/cm3[3]
when liquid (at m.p.)5.5 g/cm3
Heat of fusion21.5 kJ/mol
Heat of vaporization444 kJ/mol
Molar heat capacity24.89 J/(mol·K)
Vapor pressure
P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2101 2289 2523 2814 3187 3679
Atomic properties
Oxidation states−3, −1, 0, +1, +2, +3, +4, +5 (an amphoteric oxide)
ElectronegativityPauling scale: 1.63
Ionization energies
  • 1st: 650.9 kJ/mol
  • 2nd: 1414 kJ/mol
  • 3rd: 2830 kJ/mol
  • (more)
Atomic radiusempirical: 134 pm
Covalent radius153±8 pm
Color lines in a spectral range
Spectral lines of vanadium
Other properties
Natural occurrenceprimordial
Crystal structurebody-centered cubic (bcc) (cI2)
Lattice constant
Body-centered cubic crystal structure for vanadium
a = 302.72 pm (at 20 °C)[3]
Thermal expansion8.77×10−6/K (at 20 °C)[3]
Thermal conductivity30.7 W/(m⋅K)
Electrical resistivity197 nΩ⋅m (at 20 °C)
Magnetic orderingparamagnetic
Molar magnetic susceptibility+255.0×10−6 cm3/mol (298 K)[4]
Young's modulus128 GPa
Shear modulus47 GPa
Bulk modulus160 GPa
Speed of sound thin rod4560 m/s (at 20 °C)
Poisson ratio0.37
Mohs hardness6.7
Vickers hardness628–640 MPa
Brinell hardness600–742 MPa
CAS Number7440-62-2
History
DiscoveryAndrés Manuel del Río[5] (1801)
First isolationHenry Enfield Roscoe (1867)
Named byNils Gabriel Sefström (1830)
Isotopes of vanadium
Main isotopes Decay
abun­dance half-life (t1/2) mode pro­duct
48V synth 16 d β+ 48Ti
49V synth 330 d ε 49Ti
50V 0.25% 2.71×1017 y β+ 50Ti
51V 99.8% stable
 Category: Vanadium
| references
The Pourbaix diagram for vanadium in water.

Vanadium (/vəˈneɪdiəm/) is a chemical element that has the symbol V and atomic number 23. A soft and ductile element, vanadium naturally occurs in about 65 different minerals and is used mainly to produce certain alloys. It is one of the 26 elements found in most living organisms.

Notable characteristics

Vanadium is a soft and ductile, silver-grey metal. It has good resistance to corrosion by alkalis, sulfuric and hydrochloric acid. It oxidizes readily at about 933 K (660 C). Vanadium has good structural strength and a low fission neutron cross section, making it useful in nuclear applications. Although a metal, it shares with chromium and manganese the property of having valency oxides with acid properties.

Common oxidation states of vanadium include +2, +3, +4 and +5. A popular experiment with ammonium vanadate NH4VO3, reducing the compound with zinc metal, can demonstrate colorimetrically all four of these vanadium oxidation states. An oxidation state of +1 is rarely seen.

Applications

Approximately 80% of vanadium produced is used as ferrovanadium or as a steel additive. Other uses:

History

Vanadium (named after Vanadis, the Scandinavian goddess of beauty) was originally discovered by Andrés Manuel del Río (a Spanish-born Mexican mineralogist) in Mexico City, in 1801. He discovered the element after being sent a sample of "brown lead" ore (now named vanadinite). Through experimentation, he found it to form salts with a wide variety of colors, so he named the element panchromium (Greek: all colors). He later renamed this compound erythronium, since most of the salts turned red when heated. The French chemist Hippolyte Victor Collet-Descotils incorrectly declared that del Río's new element was only impure chromium. Del Río thought himself to be mistaken and accepted the statement of the French chemist that was also backed by del Río's friend Baron Alexander von Humboldt.[6]

In 1831, Sefström of Sweden rediscovered vanadium in a new oxide he found while working with some iron ores and later that same year Friedrich Wöhler confirmed del Río's earlier work.[7] Later, George William Featherstonhaugh, one of the first US geologists, suggested that the element should be named "rionium" after del Río, but this never happened.

Metallic vanadium was isolated by Henry Enfield Roscoe in 1867, who reduced vanadium(III) chloride VCl3 with hydrogen.[8] The name vanadium comes from Vanadis, a goddess in Scandinavian mythology, because the element has beautiful multicolored chemical compounds.[7]

Biological role

In biology, a vanadium atom is an essential component of some enzymes, particularly the vanadium nitrogenase used by some nitrogen-fixing micro-organisms. Vanadium is essential to ascidians or sea squirts in vanadium chromagen proteins. The concentration of vanadium in their blood is more than 100 times higher than the concentration of vanadium in the seawater around them. Rats and chickens are also known to require vanadium in very small amounts and deficiencies result in reduced growth and impaired reproduction.

Ten percent of the blood cell pigment of the sea cucumber is vanadium. Just as the horseshoe crab has blue blood rather than red blood (colored by iron in hemoglobin) because of copper in the hemocyanin pigment, the blood of the sea cucumber is yellow because of the vanadium in the vanabin pigment[9]. Nonetheless, there is no evidence that vanabins carry oxygen, in contrast to hemoglobin and hemocyanin.

A form of vanadium, vanadyl sulfate, seems to improve glucose control in people with type 2 diabetes.[10][11][12][13][14]

Several species of macrofungi, namely Amanita muscaria and related species, are known as effective accumulators of vanadium (up to 500 mg/kg in dry weight). Vanadium is present as an organometallic compound (called amavadine) in fungal fruit-bodies. However, the biological importance of the accumulation process is unknown.

Mineral supplement in drinking water

Most continental waters show a vanadium concentration of less than 3 ppb. However, the groundwater of Mt. Fuji contains a very high concentration of vanadium—up to 150 ppb. This vanadium is solubilized from the basalt by the groundwater. The vanadium content in Mt. Fuji becomes higher at places nearer the summit and deeper in the ground. Recently this high-vanadium water of Mt. Fuji has been sold by many companies as an agent to cope with diabetes. However, there is no concrete evidence for its efficacy. The rainbow trout living in the Mt. Fuji water showed much higher accumulation of vanadium in kidneys and bone.

Occurrence

Vanadium is never found unbound in nature but it does occur in about 65 different minerals among which are patronite VS4, vanadinite Pb5(VO4)3Cl, and carnotite K2(UO2)2(VO4)2.3H2O.

By far the greatest proportion of the world's vanadium production is sourced from vanadium-bearing magnetite found in ultramafic gabbro bodies. From these ores vanadium can be calcined to form ferrovanadium, or can be recovered from the vanadium steel smelting process which is widely used in Russia and China.

Vanadium is also present in bauxite, and in carbon containing deposits such as crude oil, coal, oil shale and tar sands. Vanadium has also been detected spectroscopically in light from the Sun and some other stars.

Much of the vanadium metal being produced is now made by calcium reduction of V2O5 in a pressure vessel. Vanadium is usually recovered as a by-product or co-product, and so world resources of the element are not really indicative of available supply.

See also category:vanadate minerals.

Isolation

Vanadium is available commercially and production of a sample in the laboratory is not normally required. Commercially, routes leading to metallic vanadium as main product are not usually required as enough is produced as byproduct in other processes.

In industry, heating of vanadium ore or residues from other processes with salt NaCl or sodium carbonate Na2CO3 at about 850°C gives sodium vanadate NaVO3. This is dissolved in water and acidified to give a red solid which in turn is melted to form a crude form of vanadium pentoxide V2O5. Reduction of vanadium pentoxide with calcium gives pure vanadium. An alternative suitable for small scales is the reduction of vanadium pentachloride VCl5 with hydrogen or magnesium. Many other methods are also in use.

Industrially, most vanadium is used as an additive to improve steels. Rather than proceed via pure vanadium metal it is often sufficient to react the crude of vanadium pentoxide V2O5 with crude iron. This produces ferrovanadium suitable for further work.

Compounds

Vanadium pentoxide V2O5 is used as a catalyst principally in the production of sulfuric acid. It is the source of vanadium used in the manufacture of ferrovanadium. It can be used as a dye and color-fixer.

Vanadyl sulfate VOSO4, also called vanadium(IV) sulfate oxide hydrate, is used as a relatively controversial dietary supplement, primarily for increasing insulin sensitivity and body-building. Whether it works for the latter purpose has not been proven, and there is some evidence that athletes who take it are merely experiencing a placebo effect.

Anhydrous VCl4 is a liquid at room temperature and reacts violently with water; it can be used, in conjunction with an appropriate nitrogen compound, for vapour deposition of hard VN layers [2]. Vanadium pentafluoride is an extremely powerful fluorinating agent, capable of perfluorinating chloroalkanes [3], and has been proposed (eg [4]) as a safe and economical substitute for XeF2; it is also liquid at room temperature.

Orthovanadate VO43- is used in biochemistry as a phosphate analogue; in protein crystallography it can be used to make phosphate binding sites very visible in electron density.

Vanadium forms polyoxometalate cluster compounds, including V10 O24.

Toxicity of vanadium compounds

The toxicity of vanadium depends on its physico-chemical state; particularly on its valence state and solubility. Tetravalent VOSO4 has been reported to be more than 5 times as toxic as trivalent V2O3 (Roschin, 1967). Vanadium compounds are poorly absorbed through the gastrointestinal system. Inhalation exposures to vanadium and vanadium compounds result primarily in adverse effects to the respiratory system (Sax, 1984; ATSDR, 1990; Ress et al., 2003; Worle-Knirsch et al., 2007). Quantitative data are, however, insufficient to derive a subchronic or chronic inhalation reference dose. Other effects have been reported on blood parameters after oral or inhalation exposures (Scibior et al., 2006; Gonzalez-Villalva et al., 2006), on liver (Kobayashi et al., 2006), neurological development in rats (Soaso and Garcia, 2007), and other organs.

There is little evidence that vanadium or vanadium compounds are reproductive toxins or teratogens. Vanadium pentoxide was reported to be carcinogenic in male rats and male and female mice by inhalation in an NTP study (Ress et al., 2003), although the interpretation of the results has recently been disputed (Duffus, 2007). Vanadium has not been classified as to carcinogenicity by the U.S. EPA (1991a).

Various oxidation states of vanadium ions

It is known that vanadium gets the oxidation states +2, +3, +4, +5. To observe the colours of these states, ammonium metavanadate (NH4VO3) can be used as a starting agent. It must be acidified beforehand so dioxovanadium(V) ion, VO2+ (yellow +5 oxidation number) is produced. In alkaline medium, the stable form of vanadium(V) state is VO3-.

Adding zinc powder and concentrated hydrochloric acid continuously, VO2+ is reduced into blue VO2+.

It can be seen that during the reaction, the mixture is green in colour as the original yellow of the +5 state and the blue of the +4 are present.

Continuously adding Zn powder and concentrated HCl, blue VO2+ is reduced to green V3+. V3+ is then reduced to violet V2+ by Zn powder and concentrated HCl again.

See also Vanadium compounds.
See also Vanadium(V) oxide.

Isotopes

Naturally occurring vanadium is composed of one stable isotope 51V and one radioactive isotope 50V with a half-life of 1.5×1017 years. 24 artificial radioisotopes have been characterized (in the range of mass number between 40 and 65) with the most stable being 49V with a half-life of 330 days, and 48V with a half-life of 15.9735 days. All of the remaining radioactive isotopes have half-lives shorter than an hour, the majority of them below 10 seconds. In 4 isotopes, metastable excited states were found (including 2 metastable states for 60V).

The primary decay mode before the most abundant stable isotope 51V is electron capture. The next most common mode is beta decay. The primary decay products before 51V are element 22 (titanium) isotopes and the primary products after are element 24 (chromium) isotopes.

Precautions

Powdered metallic vanadium is a fire hazard, and unless known otherwise, all vanadium compounds should be considered highly toxic. Generally, the higher the oxidation state of vanadium, the more toxic the compound is. The most dangerous compound is vanadium pentoxide.

The Occupational Safety and Health Administration (OSHA) has set an exposure limit of 0.05 mg/m3 for vanadium pentoxide dust and 0.1 mg/m3 for vanadium pentoxide fumes in workplace air for an 8-hour workday, 40-hour work week.

The National Institute for Occupational Safety and Health (NIOSH) has recommended that 35 mg/m3 of vanadium be considered immediately dangerous to life and health. This is the exposure level of a chemical that is likely to cause permanent health problems or death.

See also

Footnotes

  1. ^ "Standard Atomic Weights: Vanadium". CIAAW. 1977.
  2. ^ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
  3. ^ a b c Arblaster, John W. (2018). Selected Values of the Crystallographic Properties of Elements. Materials Park, Ohio: ASM International. ISBN 978-1-62708-155-9.
  4. ^ Weast, Robert (1984). CRC, Handbook of Chemistry and Physics. Boca Raton, Florida: Chemical Rubber Company Publishing. pp. E110. ISBN 0-8493-0464-4.
  5. ^ "Vanadium". Royal Society of Chemistry. Royal Society of Chemistry. Retrieved December 5, 2022.
  6. ^ Pedro Cintas (2004). "The Road to Chemical Names and Eponyms: Discovery, Priority, and Credit". Angewandte Chemie International Edition. 43 (44): 5888–5894. doi:10.1002/anie.200330074.
  7. ^ a b N. G. Sefström (1831). "Ueber das Vanadin, ein neues Metall, gefunden im Stangeneisen von Eckersholm, einer Eisenhütte, die ihr Erz von Taberg in Småland bezieht". Annalen der Physik und Chemie. 97 (1): 43–49. doi:10.1002/andp.18310970103.
  8. ^ Henry E. Roscoe (1869 – 1870). "Researches on Vanadium.--Part II". Proceedings of the Royal Society of London. 18: 37–42. {{cite journal}}: Check date values in: |year= (help)
  9. ^ Natkin, Michael (2007). "Blood Color". Science Facts. Soak (Source Of All Knowledge). Retrieved 2007-11-16.
  10. ^ Halberstam, M; et al. (1996). "Oral vanadyl sulfate improves insulin sensitivity in NIDDM but not in obese nondiabetic subjects". Diabetes. 45: 659–66. {{cite journal}}: Explicit use of et al. in: |first= (help)
  11. ^ Boden, G; et al. (1996;). "Effects of vanadyl sulfate on carbohydrate and lipid metabolism in patients with non-insulin dependent diabetes mellitus". Metabolism. 45: 1130–5. {{cite journal}}: Check date values in: |year= (help); Explicit use of et al. in: |first= (help)CS1 maint: extra punctuation (link)
  12. ^ Goldfine, AB; et al. (2000). "Metabolic effects of vanadyl sulfate in humans with non-insulin-dependent diabetes mellitus: in vivo and in vitro studies". Metabolism. 49: 400–10. {{cite journal}}: Explicit use of et al. in: |first= (help)
  13. ^ Badmaev, V; et al. (1999). "Vanadium: a review of its potential role in the fight against diabetes". Altern Complement Med. 5: 273–291. {{cite journal}}: |format= requires |url= (help); Explicit use of et al. in: |first= (help)
  14. ^ Goldwaser, I; et al. (1999). J Biol Chem. 274: 26617-26624 title = L-glutamic acid gamma-monohydroxamine. A potentiator of vanadium-evoked glucose metabolism in vitro and in vivo. {{cite journal}}: Explicit use of et al. in: |first= (help); Missing or empty |title= (help); Missing pipe in: |pages= (help)

References

  • Los Alamos National Laboratory – Vanadium
  • High vanadium content in Mt.Fuji groundwater and its relevance to the ancient biosphere by Tatsuo Hamada in Vanadium in Environment. Part 1: Chemistry and Biochemistry. Edited by Jerome O. Nriagu. Page 97-123. 1998. John Wilen & Sons, Inc.
  • Duffus JH. Carcinogenicity classification of vanadium pentoxide and inorganic vanadium compounds, the NTP study of carcinogenicity of inhaled vanadium pentoxide, and vanadium chemistry. Regul Toxicol Pharmacol 2007 Feb;47(1):110-4.
  • Gonzalez-Villalva A, Fortoul TI, Avila-Costa MR, et al. Thrombocytosis induced in mice after subacute and subchronic V2O5 inhalation. Toxicol Ind Health 2006 Apr;22(3):113-6.
  • Kobayashi K, Himeno S, Satoh M, et al. Pentavalent vanadium induces hepatic metallothionein through interleukin-6-dependent and -independent mechanisms. Toxicology 2006 Dec 7;228(2-3:162-170.
  • Ress NB, Chou BJ, Renne RA, et al. Carcinogenicity of inhaled vanadium pentoxide in F344/N rats and B6C3F1 mice. Toxicol Sci 2003 Aug;74(2):287-96.
  • Scibior A, Zaporowska H, Ostrowski J. Selected haematological and biochemical parameters of blood in rats after subchronic administration of vanadium and/or magnesium in drinking water. Arch Environ Contam Toxicol 2006 Aug;51(2):287-95.
  • Soazo M, Garcia GB. Vanadium exposure through lactation produces behavioral alterations and CNS myelin deficit in neonatal rats. Neurotoxicol Teratol 2007 Jul-Aug;29(4):503-10.
  • Worle-Knirsch JM, Kern K, Schleh C, et al. Nanoparticulate vanadium oxide potentiated vanadium toxicity in human lung cells. Environ Sci Technol 2007 Jan 1;41(1):331-6.

External links