 Discovery Information
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| Who: Walter Noddack, Ida Tacke, Otto Berg
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| When: 1925 |
| Where: Germany |
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| Name Origin
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| From the Rhines provinces of Germany. |
| "Rhenium" in different languages. |
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| Sources
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| Found in small amounts in gadolinite ((Ce,La,Nd,Y)2FeBe2Si2O10) and molybdenite (MoS2). This element is widely spread through the Earth's crust at approximately 0.001 parts per million. Annual production is
around 4.5 tons.
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| Abundance
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| Universe: 0.0002 ppm (by weight) |
| Sun: 0.0001 ppm (by weight) |
| Carbonaceous meteorite: 0.05 ppm |
| Earth's Crust: 0.0004 ppm |
| Seawater: 4 x 10-6 ppm
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| Uses
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| It is added to tungsten and molybdenum alloys and is used in refractory metal components of missiles, electronic filaments, electrical contacts, high-temperature thermocouplers, oven filaments,
electrodes, igniters for flash bulbs, jewellery, plating of metals by electrolysis and vapour-phase deposition.
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| History
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| Rhenium was the last naturally occurring element to be discovered. The existence of a yet undiscovered element at this position
in the periodic table had been predicted by Henry Moseley in 1914. It is generally considered to have been discovered by Walter Noddack, Ida Tacke, and Otto Berg in Germany. In 1925 they reported that they detected the element in platinum ore and in the mineral columbite. They also found rhenium in gadolinite ([(Fe, Mn)(Nb, Ta)2O6]) and molybdenite (MoS2). In 1928 they were able to extract 1 g of element by processing 660 kg of molybdenite.
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| The process was so complicated and the cost so high that production was discontinued until early 1950 when tungsten-rhenium and molybdenum-rhenium alloys were prepared. These alloys found important applications in industry that resulted in a great demand for the
rhenium produced from the molybdenite fraction of porphyry copper ores.
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| In 1908, Japanese chemist Masataka Ogawa announced that he discovered the 43rd element, and named it nipponium (Np) after
Japan (which is Nippon in Japanese). However, later analysis indicated the presence of rhenium (element 75), not element 43. The
symbol Np was later used for the element neptunium.
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| Notes
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| Rhenium is a metallic element that has a very high tensile strength (80,000psi), high modulus of elasticity, is virtually
insoluble in hydrochloric acid and does not oxidize or corrode in saltwater. In addition it has the widest range of valences of any element and it retains
its crystalline structure all the way to its melting point. Alloys of rhenium-molybdenum are superconductive at 10K.
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| Rhenium was the last naturally-occurring element to be discovered, and belongs to the group of ten most expensive metals on
Earth.
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