Rhenium does not occur free in nature or as a compound in a particular type of mineral. It is widely spread throughout Earth's crust at approximately 1 to 4 ppb. Commercially, rhenium is obtained through the processing of copper-sulfide ores that contain molybdenum. In this purification, the molybdenum occurs as a sulfurous sludge, which, at elevated temperatures, releases rhenium. The next step in the process is production of the ammonium salt ammonium perrhenate.
APR is the product sold to metal brokers and catalyst manufacturers. Rhenium is produced by reducing APR with hydrogen. Applications for rhenium are numerous. Because of rhenium's high resistance to poisoning from nitrogen, sulfur, and phosphorus, rhenium catalysts are used for the hydrogenation of fine chemicals and the disproportionation of alkenes. What's clear is that while rhenium may once have been missing, it's difficult to imagine the periodic table today without it!
Fred Brot is a technical service scientist for Sigma-Aldrich. He also serves as a technical writer and editor for scientific documents. Author Names M. Feroze Ahmed Donald P. Ames Peter Armbruster John T. Choppin Paul C. Chu Gerald D. Cole Thomas M. Connelly Jr. Rhenium metal is prepared by reducing ammonium perrhentate with hydrogen. Rhenium had good wear resistance and can withstand corrosion.
Rhenium wire is used in flash photography. It is used in hydrogenation of fine chemicals and as an additive to tungsten and molybdenum-based alloys. Source: Los Alamos National Laboratory. In , Masataka Ogawa found it in the mineral thorianite from Sri Lanka. He realised from lines in its atomic spectrum that it contained an unknown element. He wrongly thought it was the one directly below manganese and so his claim was discounted at the time. They concentrated it from the ore gadolinite in which it was an impurity.
Atomic data. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey.
Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled.
Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators. Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators.
Supply risk. Relative supply risk 6. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material. Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Rhenium Podcast Transcript :.
You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry. This week one of the rarest elements on earth that seems to enjoy changing the laws of nature. Rhenium is element 75 in the periodic table and in many ways a rather unusual element. It is one of the rarest elements on the Earth with an abundance of something like 1 part per million. It is also one of the densest elements, following only platinum, iridium and osmium and it is one of the highest melting point elements exceeded only by tungsten and carbon.
Rhenium sits two places below manganese in the periodic table and its existence was first predicted by Mendeleev when he first proposed his periodic table in In fact this group is unusual in that, when the periodic table was first published, it possessed only one known element, manganese, with at least two gaps below it. The first gap was eventually filled by element 43 technetium, the second gap was filled by rhenium. But rhenium was the first to be discovered.
In the course of an extraction of epic proportions, they processed about kg of the ore molybdenite in order to get just one gram of rhenium.
These days rhenium is extracted more efficiently as the bi-product of the processes for the purification of molybdenum and copper, since rhenium often occurs as an impurity in the ores of these elements. The discoverers called their element, rhenium, after the Latin name Rhenus for the river Rhine close to the place where they were working.
In fact the Noddacks and Berg believed that they had also isolated the other element missing from group 7, or element 43, that eventually became known as technetium, but it was not to be. As recently as the early years of the 21st century some researchers from Belgium and the US re-analyzed the X-ray evidence from the Noddacks and argued that they had in fact isolated element But these claims have been hotly debated by many radiochemists and physicists and now have been finally laid to rest.
But by an odd twist of fate, a Japanese chemist, Masataka Ogawa believed that he had isolated element 43 and called it nipponium back in His claim too was largely discredited but as recently as it has emerged that he had in fact isolated rhenium well before the Noddacks. Until quite recently no mineral containing rhenium combined with just a non-metal had ever been found.
Not until that is, when a team of Russian scientists discovered rhenium disulphide at the mouth of a volcano on an islands off the east coast of Russia between the Kamchatka peninsula and the Japanese islands. The chemistry of rhenium is also rather interesting. Now here is another oddity. Until the early s it was believed that three bonds between any two atoms was as high as nature could go, as in the case of the nitrogen-nitrogen triple bond for example.
But in Albert Cotton and co-workers in the USA discovered the existence of a metal-metal quadruple bond. More recently an especially simple compound of rhenium, rhenium dibromide, has attracted a great deal of scientific attention because it is one of the hardest of all known substances.
And unlike other super-hard materials, like diamond, it does not have to be manufactured under high pressure conditions. But what else is rhenium good for? What are some other applications? Well there are many of them. A good deal of the rhenium extracted is made into super-alloys to be used for parts in jet engines.
Not surprisingly for a transition metal, rhenium is also a good catalyst. In fact a combination of rhenium and platinum make up the catalyst of choice in the very important process of making lead-free and high-octane petrol. Rhenium catalysts are especially resistant to chemical attack from nitrogen, phosphorus, and sulfur, which also makes them useful in hydrogenation reactions in various industrial processes.
And just to go back to the Noddacks, and in particular Ida Noddack, it was she who first proposed in that nuclear fission might be possible as the result of the break up of a nucleus into fragments but her speculation was ignored and it had to wait until when Hahn, Strassmann and Meitner really discovered fission. Why was Noddack ignored? The most popular view seems to be that it was because her reputation had been damaged by her falsely announcing the discovery of element 43 in addition to the correct discovery of rhenium.
So its one of the hardest of all known substances, has a variety of oxidation states, and has the ability to make quadruple bonds, certainly a rule breaker. Next week, a colourful luminous element.
This bright colour renders terbium compounds particularly useful as colour phosphors in lighting applications, e. And Manchester University's Louise Natrajan will be filling us in on the colourful story of terbium in next week's Chemistry in its element. Until then I'm Meera Senthilingam and thank you for listening. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists.
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