Chemical Properties
Vanadium is a soft, ductile, silver-gray metal. It has good resistance to corrosion by alkalis, sulfuric and hydrochloric acid, and salt water. Vanadium metal, sheet, strip, foil, bar, wire, and tubing are used in industries. It is used in high-temperature service, in the production of rust-resistant, high-speed tools, and is an important carbide stabilizer in making steels. In fact, most vanadium is used as an additive to improve steels. Vanadium steel is especially strong and hard, with improved resistance to shock. Vanadium pentoxide (V2O5) is perhaps vanadium’s most useful compound. It is used as a mordant—a material that permanently fi xes dyes to fabrics. Vanadium pentoxide is used as a catalyst in chemical reactions and in the manufacture of ceramics. Vanadium pentoxide can also be mixed with gallium to form superconductive magnets.
Uses
Alloying agent in manufacture of rust-resistant vanadium steel.
General Description
Silvery-whitish powder. Resists corrosion.
Reactivity Profile
VANADIUM (FUME OR DUST)(7440-62-2) is a reducing agent. Finely divided form favors rapid or explosive reactions with oxidizing agents such as air or oxygen. Reacts exothermically with compounds having active hydrogen atoms (such as acids and water) to form flammable hydrogen gas and caustic products. The reactions are much less vigorous than the similar reactions of alkali metals. Can catalyze polymerization reactions in several classes of organic compounds; these polymerizations sometimes proceed rapidly or even explosively. Vanadium is used as a catalyst in the production of synthetic rubber and sulfuric acid.
Air & Water Reactions
Not oxidized by air and not appreciably affected by moisture at ordinary temperatures. Some hydrogen gas may be created however this would proceed slowly under ambient conditions. Insoluble in water.
Health Hazard
Exposures to high levels of vanadium cause harmful health effects. The major effects from breathing high levels of vanadium are on the lungs, throat, and eyes. Workers who breathe vanadium for short and long periods show lung irritation, coughing, wheezing, chest pain, runny nose, and sore throat. Prolonged period of exposures to respirable dusts and vanadium fume have caused potential symptoms of toxicity among occupational workers. The symptoms of poisoning include, but are not limited to, irritation of the eyes and throat, green tongue, metallic taste, sore throat, cough, drowsiness, wheezing, bronchitis, abdominal cramps, nausea, vomiting, diarrhea, respiratory distress, pulmonary edema, bronchial damage, epistaxis (bloody nose), eczema, conjunctivitis, headache, dry mouth, dizziness, nervousness, insomnia, and tremor. It is not classifi able as a human carcinogen. Vanadium is a natural component of fuel oil, and workers have developed vanadium poisoning during cleaning operations on oil-fi red furnaces.
Potential Exposure
Vanadium is used as a catalyst in the
production of synthetic rubber and sulfuric acid. Most of the
vanadium produced is used in ferrovanadium and of this the
majority is used in high speed and other alloy steels with
only small amounts in tool or structural steels. It is usually
combined with chromium, nickel, manganese, boron, and
tungsten in steel alloys.
First aid
If this chemical gets into the eyes, remove any
contact lenses at once and irrigate immediately for at least
15 minutes, occasionally lifting upper and lower lids. Seek
medical attention immediately. If this chemical contacts the
skin, remove contaminated clothing and wash immediately
with soap and water. Seek medical attention immediately.
If this chemical has been inhaled, remove from exposure,
begin rescue breathing (using universal precautions, including
resuscitation mask) if breathing has stopped and CPR if
heart action has stopped. Transfer promptly to a medical
facility. When this chemical has been swallowed, get medical
attention. Give large quantities of water and induce
vomiting. Do not make an unconscious person vomit
Shipping
UN3285 Vanadium compound, n.o.s., Hazard
Class: 6.1; Labels: 6.1-Poisonous materials, Technical Name
Required. This number includes vanadium fume or dust.
Incompatibilities
Dust may form explosive mixture with
air. Dust, fume, and powders are a strong reducing agent;
incompatible with oxidizers (chlorates, nitrates, peroxides,
permanganates, perchlorates, chlorine, bromine, fluorine,
etc.); contact may cause fires or explosions. Keep away
from alkaline materials, strong bases, strong acids, oxoacids,
epoxides, bromine trifluoride, lithium, nitryl fluoride,
chlorine trifluoride.
Description
Vanadium was discovered in 1830 in Mexico by Andreas Manuel
del Rio. It is present at 0.01% in earth’s crust and found in about
65 different minerals. Vanadium is released naturally into the air
through the formation of continental dust, marine aerosols, and
volcanic emissions. The natural release of vanadium into water
and soils occurs primarily as a result of weathering of rocks and
soil erosion. Anthropogenic sources include the combustion of
fossil fuels, particularly residual fuel oils, which constitute the
single largest overall release of vanadium into the atmosphere.
Deposition of atmospheric vanadium is also an important
source both near and far from industrial plants burning residual
fuel oils rich in vanadium. Other anthropogenic sources include
leachates from mining tailings, vanadium-enriched slag heaps,
municipal sewage sludge, and certain fertilizers. Natural releases
to water and soil are far greater overall than anthropogenic
releases to the atmosphere.
Physical properties
Vanadium is a silvery whitish-gray metal that is somewhat heavier than aluminum, butlighter than iron. It is ductile and can be worked into various shapes. It is like other transitionmetals in the way that some electrons from the next-to-outermost shell can bond with otherelements. Vanadium forms many complicated compounds as a result of variable valences. Thisattribute is responsible for the four oxidation states of its ions that enable it to combine withmost nonmetals and to at times even act as a nonmetal. Vanadium’s melting point is 1890°C,its boiling point is 3380°C, and its density is 6.11 g/cm3.
Isotopes
There are 27 isotopes of vanadium. Only vanadium-51 is stable and makes up99.75% of the total vanadium on Earth. The other 0.25% of the vanadium found onEarth is from the radioisotope vanadium-50, which has such a lon+17years that it is considered stable. The other radioactive isotopes have half-lives rangingfrom 150 nanoseconds to one year.
Origin of Name
Named after the Scandinavian mythological goddess Vanadis because
of the many colors exhibited by vanadium’s compounds.
Occurrence
Vanadium is not found in its pure state. Small amounts of vanadium can be found inphosphate rocks and some iron ores. Most of it is recovered from two minerals: vanadinite,which is a compound of lead and chlorine plus some vanadium oxide, and carnotite, a mineral containing uranium, potassium, and an oxide of vanadium. Because of its four oxidationstates and its ability to act as both a metal and a nonmetal, vanadium is known to chemicallycombine with over 55 different elements.Vanadium’s principal ores are roscoelite, patronite, vanadinite, and carnotite, which arefound in the states of Idaho, Montana, Arkansas, and Arizona as well as in Mexico and Peru.It is also a by-product from the production of phosphate ores.
Characteristics
Vanadium is an excellent alloy metal with iron that produces hard, strong, corrosion-resistant steel that resists most acids and alkali. It is even more resistant to seawater corrosion thanis stainless steel. Vanadium is difficult to prepare in a pure form in large amounts. Impureforms seem to work as well as a very pure form of the metal when used as an alloy. Whenworked as a metal, it must be heated in an inert atmosphere because it will readily oxidize.
Definition
A silvery transition
element occurring in complex ores in
small quantities. It is used in alloy steels.
Vanadium forms compounds with oxidation
states +5, +4, +3, and +2. It forms colored ions.
Symbol: V; m.p. 1890°C; b.p. 3380°C;
r.d. 6.1 (20°C); p.n. 23; r.a.m. 50.94.
Definition
Symbol V. A silverywhite metallic transition element; a.n. 23; r.a.m. 50.94; r.d. 5.96; m.p. 1890°C; b.p. 3380°C. It occurs in a number of complex ores, including vanadinite (Pb5Cl(VO4)3) and carnotite (K2(ClO2)2(VO4)2). The pure metal can be obtained by reducing the oxide with calcium. The element is used in a large number of alloy steels. Chemically, it reacts with nonmetals at high temperatures but is not affected by hydrochloric acid or alkalis. It forms a range of complexes with oxidation states from +2 to +5. Vanadium was discovered in 1801 by Andrés del Rio (1764–1849), who allowed himself to be persuaded that what he had discovered was an impure form of chromium. The element was rediscovered and named by Nils Sefström (1787–1854) in 1880.
Production Methods
World resources of vanadium exceed 63 million tons. Vanadium occurs in deposits of phosphate rock, titaniferous magnetite, and uraniferous sandstone and siltstone, in which it constitutes less than 2% of the host rock. Signi?cant amounts are also present in bauxite and carboniferous materials,suchascoal,crudeoil,oilshale,andtarsands(19).
Vanadium is usually recovered as a by-product or a coproduct during the extraction of other compounds, such as iron, titanium, phosphate, or petroleum. It is extracted from carnotite, phosphate rock deposits, titaniferous magnetites, and vanadiferous clays. A process called salt roasting during the initial stage of extraction produces the oxide concentrate. The ores, petroleum residues, iodide thermal decomposition products, and slags formed during ferrovanadate production are crushed, dried, ?nely ground, mixed with a sodium salt, and roasted. The hot ore, containing sodium metavanadate, precipitates as a red cake, is then mixedwithsulfuricacid,andtheresultantprecipitateisdried to form vanadium pentoxide. The vanadium pentoxide can then be processed further to form the required vanadium compound. Pure vanadium is dif?cult to obtain as it tends to be readily contaminated with other elements. Methods to extract pure vanadium include iodide re?ning, electrolytic re?ning in a fused salt, and electrotransport. The highest purity vanadium has been puri?ed by the electrotransport technique. High-purity ductile vanadium can be obtainedbyreductionofvanadiumchloridewithmagnesium or with magnesium-sodium mixtures. Much of thevanadium metal is now produced by calcium reduction of V2O5 in a pressure vessel.
Purification Methods
Clean the metal by rapid exposure consecutively to HNO3, HCl, HF, de-ionised water and reagent grade acetone, then dry it in a vacuum desiccator. [Brauer in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol II pp 1252-1255 1965.]
Hazard
Vanadium powder, dust, and most of its oxide compounds are explosive when exposedto heat and air. They are also toxic when inhaled. Vanadium chloride compounds are strongirritants to the skin and poisonous when ingested.
Many of its compounds must be stored in a dry, oxygen-free atmosphere or in containersof inert gas. Protective clothing and goggles should be worn when handling vanadium, as wellas with most of the other transition elements.
Flammability and Explosibility
Nonflammable
Agricultural Uses
Vanadium (V) is a silvery-white, metallic, transition
element of Group 5 of the Periodic Table and
exhibits a range of valencies from +2 to +5. The ores
containing vanadium include vanadite and carnotite.
The pure metal, formed by the reduction of vanadium
oxide with calcium, is generally used as an alloying
element for steel and iron. Several vanadium compounds
are used as oxidation catalysts. They are also used as
coloring agents in the ceramic industry.
Vanadium comes under the category of beneficial
elements which are non-essential but beneficial to plant
growth. It is a very useful nutrient for the green alga Scenedesmus, but the exact amount of vanadium needed
for the growth of higher plants is yet to be established.
Vanadium may replace molybdenum to some extent
in nitrogen fixation by micro-organisms such as
Azotobacter and Rhizobium. An increase in growth due to
vanadium is seen in asparagus, rice, lettuce, barley and
corn. It has also been speculated that vanadium may
function in biological oxidation-reduction reactions.
Vanadium stimulates growth and nitrogenase activity
in Anabaena variabilis in the absence of molybdenum.
Low concentrations of vanadium are beneficial for the
optimal growth of micro-organisms and higher plants.
Generally, the concentration of vanadium in plants is
about 1 ppm.
Industrial uses
Vanadium is a member of the d-block metals and belongs to group 5 of the periodic table of elements. Vanadium can be found in the earth s crust in numerous minerals and is isolated from ores mostly as a by-product. Its main application is in the steel industry, where it is used as an alloy in combination with iron. Vanadium pentaoxide is also being used as a catalyst for the production of sulfuric acid. The metal vanadium has very similar properties to titanium. Therefore, it is not surprising that its metallocene, vanadium dichloride, was also subjected to research as a potential anticancer agent. Vanadium is an essential trace metal in the human body, but still very little is known about its biological function. Vanadium is mainly found in its ionic state bound to proteins.
Veterinary Drugs and Treatments
Vanadium supplementation may be useful in the adjunctive treatment
of diabetes mellitus, particularly in cats. There is controversy
whether or not this treatment is beneficial.
Carcinogenicity
The results of 2-year NTP inhalation study on F344/N rats (at concentrations of 0, 5, 1, or 2mg/m3) and B6C3F1 mice (at concentrations of 1, 2, or 4mg/m3)exposedfor6hperdayfor5daysperweekindicate clear evidence of carcinogenic activity of vanadium pentoxide based on the occurrence of alveolar/bronchiolar neoplasms. Exposure to V2O5 caused a spectrum of nonneoplastic lesions in the respiratory tract (nose, larynx, and lung), including alveolar and bronchiolar epithelium hyperplasia, in?ammation, ?brosis, and alveolar histiocytosis of the lung in male and female rats and mice, and an unusual squamous metaplasia of the lung in male and female rats. Hyperplasiaofthebronchiallymphnodesoccurredinfemale mice. In a 16-day inhalation study in rat, alveolar and bronchiolar epithelial hyperplasia was observed in most rats exposed to 2 or 4mg/m3 V2O5 on days 6 and 13.
Toxicity evaluation
In the consolidated form, vanadium metal and its alloys may
pose no particular health or safety hazard; however, the toxicity
of vanadium alloys may be a function of other components of
the alloy. Vanadium compounds have been proved to be
associated with the pathogenesis of some human diseases and
also in the maintenance of normal body functions. Salts of
vanadium interfere with many enzyme systems, for example,
ATPases, protein kinases, ribonucleases, and phosphatases.
Vanadium may also be an essential trace element, contributing
to glucose balance; however, the importance of this element as
a micronutrient is yet to be unequivocally accepted. Vanadium
deficiency has been associated with disturbances in physiological
functions, for instance, thyroid, glucose, and lipid
metabolism. Vanadate (VO-3) mimics the action of insulin in
target tissues and is a potential inhibitor of the sodium pump.
Vanadium toxicity is enhanced by dietary zinc. Several genes
are regulated by this element or by its compounds, including
those for tumor necrosis factor-alpha, interleukin-8, activator
protein-1, ras, c-raf-1, Mitogen activated protein kinase, p53,
and nuclear factor kappa B. When inhaled, vanadium is toxic to
alveolar macrophages and therefore may impair pulmonary
resistance to infection and clearance of particulate matter. An
increase in inflammatory cells of the nasal mucosa has been
observed in workers exposed to vanadium.
