Superphosphate is a fertilizer produced by the action of concentrated sulfuric acid on powdered phosphate rock. Fertilizers ( also spelt fertiliser are chemical compounds given to Plants to promote growth they are usually applied either through the soil for uptake by plant Sulfuric (or sulphuric acid, H 2 S[[oxygen O]]4 is a strong Mineral acid. Phosphate rock or Phosphorite is a general description applied to several kinds of rock which contain significant concentrations of Phosphate minerals

Ca₃(PO₄)₂ + 2H₂SO₄ → Ca(H₂PO₄)₂ + 2CaSO₄

History and development

In the 1840s, scientists found that coprolites could be dissolved in sulfuric acid to produce what became known as superphosphate. A Coprolite is Fossilized animal dung Coprolites are classified as trace fossils as opposed to body fossils as they give evidence for the animal's behaviour (in

In 1840, Justus Von Liebig wrote, "The crops on the field diminish or increase in exact proportion to the diminution or increase of the mineral substances conveyed to it in manure. Justus von Liebig ( May 12, 1803 &ndash April 18, 1873) was a German Chemist " Von Liebig was the first to discover that phosphate of lime in bone meal could be rendered more readily available to plants by treatment with sulfuric acid. Sir John Bennett Lawes about the same time discovered that phosphate rock underwent the same reaction and could be used as a source ingredient. "Sir John Lawes" redirects here Distinguish from Sir John Lawes (School

Simply put, insoluble tricalcicphosphate is converted to soluble monocalcicphosphate by reaction with sulphuric acid.

Bennett Lawes was the first to manufacture superphosphate at his factory in Deptford, England in 1842.

A large market for superphosphate was created in the second half of the 20th century by the development of aerial topdressing in New Zealand which allowed superphosphate to be spread economically over large areas. Aerial topdressing is the spreading of fertilisers such as Superphosphate over Farmland with the use of Aircraft. New Zealand is an Island country in the south-western Pacific Ocean comprising two main landmasses (the North Island and the South Island

Limestone pinnacles left on Nauru after phosphate mining

Superphosphate can be created naturally in large quantities by the action of guano, or bird feces, resulting in deposits around sea bird colonies which can be mined. Limestone is a Sedimentary rock composed largely of the Mineral Calcite ( Calcium carbonate: CaCO3 Guano (from the Quechua 'wanu' via Spanish) is the Feces of Seabirds Bats and seals The most famous mining site is the island of Nauru in the South Pacific much of the "soil" from which was mined, creating temporary wealth for the inhabitants, but destroying their environment. Nauru, officially the Republic of Nauru, is an Island nation in the Micronesian South Pacific. The Pacific Ocean is the largest of the Earth 's Oceanic divisions

See also

• triple superphosphate

References

• Yara corporate History Accessed May 2007

External links