Vanadium cycle

Values are in 10^9 g/yr.[1] Vanadium is a relatively ample trace metal which enters surfaces through chemical weathering. Vanadium can be released into the atmosphere through volcanic ash, coal and petroleum pollution, or fires. Vanadium enters back into the earth through sedimentation and the cycle begins again. The two largest mechanisms in the vanadium cycle include rock weathering and sedimentation.

The global vanadium cycle is controlled by physical and chemical processes that drive the exchange of vanadium between its two main reservoirs: the upper continental crust and the ocean.[1] Anthropogenic processes such as coal and petroleum production release vanadium to the atmosphere.

Sources

Natural sources

Vanadium is a trace metal that is relatively abundant in the Earth (~100 part per million in the upper crust).[1] Vanadium is mobilized from minerals through weathering and transported to the ocean. Vanadium can enter the atmosphere through wind erosion and volcanic emissions[1] and will remain there until it is removed by precipitation.[1]

Anthropogenic sources

Human activity has increased the amount of vanadium emissions to the atmosphere.[2] Vanadium is abundant in fossil fuels because it is incorporated in porphyrins during organic matter degradation.[3] Coal and petroleum factory pollution release significant vanadium to the atmosphere.[1] Vanadium is also mined and using for industrial purposes including for steel reinforcement, electronics, and batteries.[1]

Sink

Vanadium is removed from the ocean by burial marine sediments and incorporation into iron oxides at hydrothermal vents.[1][4]

Biological processes

Biological processes play a relatively minor role in the global vanadium cycle. Vanadium bromoperoxidase is present in some marine bacteria and algae.[5] Vanadium can also takes the place of molybdenum in alternative nitrogenases.[6]

References

1. Schlesinger, William H.; Klein, Emily M.; Vengosh, Avner (2017). "Global biogeochemical cycle of vanadium". Proceedings of the National Academy of Sciences. 114 (52): E11092 – E11100. doi:10.1073/pnas.1715500114. ISSN 0027-8424. PMC 5748214. PMID 29229856.
2. Hope, Bruce K. (1997). "An assessment of the global impact of anthropogenic vanadium". Biogeochemistry. 37 (1): 1–13. doi:10.1023/A:1005761904149. ISSN 1573-515X. S2CID 93183351.
3. Zhao, Xu; Xu, Chunming; Shi, Quan (2016), Xu, Chunming; Shi, Quan (eds.), "Porphyrins in Heavy Petroleums: A Review", Structure and Modeling of Complex Petroleum Mixtures, Structure and Bonding, Cham: Springer International Publishing, pp. 39–70, doi:10.1007/430_2015_189, ISBN 978-3-319-32321-3
4. Trefry, John H.; Metz, Simone (1989). "Role of hydrothermal precipitates in the geochemical cycling of vanadium". Nature. 342 (6249): 531–533. Bibcode:1989Natur.342..531T. doi:10.1038/342531a0. ISSN 1476-4687. S2CID 4351410.
5. Butler, Alison (1998). "Vanadium haloperoxidases". Current Opinion in Chemical Biology. 2 (2): 279–285. doi:10.1016/S1367-5931(98)80070-7. ISSN 1367-5931. PMID 9667930.
6. Eady, Robert R. (1996). "Structure−Function Relationships of Alternative Nitrogenases". Chemical Reviews. 96 (7): 3013–3030. doi:10.1021/cr950057h. ISSN 0009-2665. PMID 11848850.