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DESIGNATIONS
| CAS No.: | 7440-62-2 | 1314-62-1 |
| Registry name: | Vanadium | Vanadium pentoxide |
| Chemical name: | Vanadium | Vanadium pentoxide |
| Synonyms, Trade names: | Vanadium | Vanadium(V)oxide, divanadium pentoxide, vanadic acid anhydride, vanadic anhydride, vanadium pentaoxide |
| Chemical name German): | Vanadium | Vanadium pentoxid |
| Chemical name (French): | Vanadium | Pentoxyde de vanadium, anhydride vanadique, pentaoxyde de vanadium |
| Appearance: | steely grey, ductile metal | yellow to orange, crystalline powder or dark grey to brown lumps; odourless and tasteless |
BASIC CHEMICAL AND PHYSICAL DATA
| Empirical formula: | V | V2O5 |
| Rel. molecular mass: | 50.94 g | 181.88 g |
| Density: | 6.11 g/cm3 at 18.7°C | 3.357 g/cm3 |
| Relative gas density: | ||
| Boiling point: | 3380°C | 1750°C (decomposition) |
| Melting point: | 1930°C | 690°C |
| Flash point: | not combustible; promotes the combustion of other combustible substances | |
| Solvolysis/solubility: | insoluble in water, hydrochloric and sulphuric acid as well as in alkali lye at normal temperature, soluble in hydrofluoric and nitric acid | 0.005 g/l at 20°C in water, soluble in concentrated acids and lyes |
ORIGIN AND USE
Usage:
Roughly 90% of vanadium compounds are used as alloying elements
(80% in the form of ferrous vanadium and 9% as non-ferrous
compounds in the aerospace industry). The pure metal serves as
jacket material for nuclear fuel elements. Further use is as a
catalyst, especially V2O5 in the production
of sulphuric acid.
Origin/derivation:
Vanadium is found throughout the world and makes up 0.015% of the
Earth's crust. The largest natural deposits are found in South
Africa (42.2%), Russia (39.2%) and China (12.7%). Depending on
location, the geogenic concentration in water fluctuates between
0.2 and 100 m g/l in freshwater and
between 0.2 and 29 µg/l in seawater. The ocean bed serves as a
long-term sink. Natural deposits in coal and crude oil vary
between 1 and 1500 mg/kg (WHO, 1987). It is estimated that some
65,000 t are released into the environment each year by natural
emissions (volcanoes, etc.) and 200,000 t by human activities
(chiefly in metalworking).
Production figures:
| 1979: | 29,700 t | acc. DVGW, 1985 |
| 1981: | 35,000 t | acc. WHO, 1987 |
| 1980-84: | 34-46,000 t | acc. WHO, 1988 |
| 1984 | 33,300 t | acc. RÖMPP, 1988 |
The principal producers are Chile, Finland, Namibia, Norway, South Africa, Russia and the USA.
Toxicity
| Vanadium pentoxide: | ||
| Mouse | LD50 23.4 mg/kg, oral | acc. WHO, 1988 |
| Rat | LC50 70 mg/m3, inhalation | acc. WHO, 1988 |
| Rat | LD 10 mg/kg, oral | acc. WHO, 1988 |
| Cat | LC50 500 mg/m3, inhalation | acc. WHO, 1988 |
| Rabbit | LC 205 mg/m3, inhalation | acc. WHO, 1988 |
| Ammonium vanadate: | ||
| Mouse | LD50 10 mg/kg, oral | acc. WHO, 1988 |
| Vanadium trichloride: | ||
| Mouse | LD50 24 mg/kg, oral | acc. WHO, 1988 |
| Vanadium dibromide: | ||
| Mouse | LD50 88 mg/kg, oral | acc. WHO, 1988 |
| Vanadium sulphate: | ||
| Rat | LD 10 mg/kg, oral | acc. WHO, 1988 |
| Rabbit | LD50 59.1 mg/kg, subcutaneous | acc. WHO, 1988 |
| Guinea pig | LD 800 mg/kg, subcutaneous | acc. WHO, 1988 |
| Guinea pig | LD50 560 mg/kg | acc. WHO, 1988 |
Characteristic effects:
Humans/mammals: Vanadium pentoxide irritates the skin and mucous membranes (0.1 mg/m3 after 8 hours) and acts as a blood, liver and kidney poison. Symptoms of chronic exposure are bronchitis, pneumonia, anaemia, liver and kidney damage (concentrations of 0.1 - 0.4 mg/m3 during 10 years may result in changes in the nasal mucous membranes, chronic bronchitis and discolouration of the tongue; acc. HORN, 1989). The effect depends on the particle size: aerosols > 5 m m cannot penetrate the lungs. 40-60% are excreted via the kidneys after 1-3 days with 10-12% being excreted via the intestines. Vanadium pentoxide inhibits enzymes and prevents the synthesis of ascorbic and fatty acids in addition to affecting DNA (HORN, 1989).
ENVIRONMENTAL BEHAVIOUR
Water:
Vanadium compounds are denser than water and sink to the bottom.
Vanadium pentoxide slowly dissolves in a large volume of water
and forms toxic mixtures. Vanadium trichloride, vanadium
tetrachloride and vanadium oxytrichloride react with water when
exposed to heat to form toxic and irritating hydrochloric acid
vapours which in turn form a white mist over the water surface.
Air:
The atmosphere represents a transport medium. Vanadium pentoxide
is a reactive solid which promotes the combustion of other
combustible substances. Vanadium trichloride forms toxic mixtures
in air which decompose vigorously in contact with moisture and
form corrosive hydrogen chloride. Decomposition to chlorine gas
or hydrogen chloride gas occurs at high temperatures. Vanadium
tetrachloride and vanadium oxytrichloride are corrosive,
non-combustible liquids, which, when exposed to heat, likewise
form corrosive mists made up of vanadium pentoxide, hydrogen
chloride gas or hydrochloric acid. These are denser than air and
creep along the ground. Vanadium tetrachloride reacts vigorously
in water to form corrosive vanadium trichloride, vanadium
oxytrichloride and hydrochloric acid.
Soil:
Vanadium compounds are geogenic and ubiquitous. Vanadium is
an essential trace element whose compounds are absorbed by plants
and incorporated into their growth process. Vanadium thus finds
its way from the soil into the food chain.
Degradation, decomposition products, half-life:
When exposed to light and heat, most vanadium compounds
decompose to form corrosive vapours or gases. Contact with water
usually produces vigorous reactions in which corrosive vapours
and gases are likewise formed.
Food chain:
Plants and animals incorporate vanadium as an essential trace
element. The daily intake with foodstuffs is estimated at 100 m g for humans with most of the vanadium
being excreted again without resorption.
ENVIRONMENTAL STANDARDS
| Medium/ acceptor |
Sector | Country/organ. | Status | Value |
Cat. | Remarks | Source |
| Water: | Surface | D | G |
0.05 mg/l |
For treatment | (DVGW, 1985) | |
| Irrigation | USA | 10 mg/l |
Short-time value | (DVGW, 1985) | |||
| Soil: | D | G | 50 mg/kg |
(KLOKE, 1988) | |||
| Air: | Emiss. | D | L | 5 mg/m3 |
mass flow > 25 g/h1) | acc. TA Luft, 1986 | |
| DDR | (L) | 0.002 mg/m3 |
V2O5, long-time value | acc. HORN et al., 1989 | |||
| Workp | AUS | (L) | 0.05 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | B | (L) | 0.05 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | D | L | 0.05 mg/m3 |
MAK | V2O5 (fine dust) | acc. BAUM, 1988 | |
| Workp | CH | (L) | 0.1 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | CS | (L) | 0.1 mg/m3 |
V2O5 (smoke), average | acc. MERIAN, 1984 | ||
| Workp | CS | (L) | 0.3 mg/m3 |
V2O5 (smoke), short term | acc. MERIAN, 1984 | ||
| Workp | CS | (L) | 1.5 mg/m3 |
Dust | acc. WHO, 1988 | ||
| Workp | DDR | (L) | 0.1 mg/m3 |
V2O5 (smoke) | acc. HORN et al., 1989 | ||
| Workp | DDR | (L) | 0.5 mg/m3 |
V2O5 (dust), short time | acc. HORN et al., 1989 | ||
| Workp | DDR | (L) | 0.002 mg/m3 |
V2O5 (dust), long time | acc. HORN et al., 1989 | ||
| Workp | H | (L) | 0.1 mg/m3 |
V2O5 (smoke) | acc. WHO, 1988 | ||
| Workp | I | G | 0.015 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | J | (L) | 0.1 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | NL | (L) | 0.05 mg/m3 |
V2O5 (smoke) | acc. WHO, 1988 | ||
| Workp | RO | (L) | 0.1 mg/m3 |
V2O5 (smoke), short time | acc. WHO, 1988 | ||
| Workp | S | (L) | 0.5 mg/m3 |
V2O5 (dusts) | acc. ACGIH, 1982 | ||
| Workp | S | (L) | 0.05 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | SF | (L) | 0.05 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | SU | (L) | 0.002 mg/m3 |
24 h, V2O5 | acc. STERN, 1986 | ||
| Workp | SU | (L) | 0.1 mg/m3 |
V2O5 (smoke) | acc. MERIAN, 1984 | ||
| Workp | SU | (L) | 0.5 mg/m3 |
V2O3 | acc. KETTNER, 1979 | ||
| Workp | USA | (L) | 0.05 mg/m3 |
TWA | V2O5 (smoke/ dusts) | acc. ACGIH, 1986 | |
| Workp | YU | (L) | 0.1 mg/m3 |
V2O5 (smoke) | acc. WHO, 1988 |
Note:
Limit and approximate values generally exist for the sum total of
all vanadium compounds and are given in V2O5
1) dustlike V and its compounds, stated as V
Comparison/reference values
| Medium/origin | Country | Value | Source | |
| Water: | ||||
| Lake Constance (Überlingen, 1973-74) | 1.1-1.9 µg/l | acc. DVGW, 1985 | ||
| Rhine (Mannheim, 1971-74) | 0.9-11.6 µg/l | acc. DVGW, 1985 | ||
| Rhine (Mainz, 1971-74) | 1.6- 3 µg/l | acc. DVGW, 1985 | ||
| Rhine (Wiesbaden, 1971-74) | 0.1-10.3 µg/l | acc. DVGW, 1985 | ||
| Main (Ottendorf, 1971-73) | 0.2-9.6 µg/l | acc. DVGW, 1985 | ||
| Main (Kostheim, 1971-73) | 0.9-16 µg/l | acc. DVGW, 1985 | ||
| Ruhr (Echthausen, 1983) | 0.2-1.2 µg/l | acc. DVGW, 1985 | ||
| Seawater | 0.2-29 µg/l | acc. DVGW, 1985 | ||
| Drinking water (USA, 1962, 100 cities) | n.d.--70 µg/l | acc. DVGW, 1985 | ||
| Soil/sediment: | ||||
| Various soils (mean) | 100 mg/kg | acc. DVGW, 1985 | ||
| Various soils | 1-680 mg/kg | acc. WHO, 1988 | ||
| Coal (mean) | 30 mg/kg | acc. DVGW, 1985 | ||
| Oil (mean) | 50 mg/kg | acc. DVGW, 1985 | ||
| Air: | ||||
| South Pole | 0.001-0.002 ng/m3 | acc. WHO, 1988 | ||
| Rural areas | CDN | 0.21-1.9 ng/m3 | acc. WHO, 1988 | |
| Outdoors | 0.02-13 m g/m3 V2O5 | acc. HORN, 1989 | ||
| Animals: | ||||
| Molluscs | 0.7 mg/kg | acc. WHO, 1988 | ||
| Crustaceans | 0.4 mg/kg | acc. WHO, 1988 | ||
| Insects | 0.15 mg/kg | acc. WHO, 1988 | ||
| Fish | 0.14 mg/kg | acc. WHO, 1988 | ||
| Mammals | 0.4 mg/kg | acc. WHO, 1988 | ||
Assessment/comments
There are still no clear-cut results on the effects of the majority of vanadium compounds. Therefore, attempts should be made to avoid any possible impacts caused by them.