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Properties and Applications of Molybdenum
Published in C. K. Gupta, Extractive Metallurgy of Molybdenum, 2017
Unlike molybdenum, rhenium’s principal market is in catalysts. Its high selectivity for hydrogenation and dehydrogenation reactions, its high temperature stability, and its good resistance to sulfur are among the important advantages of rhenium as a catalyst. Rhenium has found applications particularly in reforming by which the low octane naphthas are converted into high octane components for gasoline. Besides the uses of rhenium in catalysis in general and oil reforming in particular, there are a number of other uses, too. They include the use of rhenium alloys for corrosion-resistant and hard-wearing parts, elements which are exposed to high temperatures such as lamp filaments, electron tubes, mass spectrographs, thermocouples, and heating elements. The main alloys of rhenium are with molybdenum, tungsten, platinum, chromium, tantalum, nickel, and cobalt. Rhenium coatings are used to reduce wear and corrosion of some surfaces. Examples of such coatings are found in electrical contacts, in plasma coatings on copper X-ray targets and marine engine magnets, and in aerospace technology. The addition of rhenium to tungsten or molybdenum alloys enhances their ductility considerably and allows production of better filaments for lamps or heating elements. Rhenium is also used extensively in pen nibs and pen points, record playing needles, and make and break contacts. In these applications, the presence of rhenium considerably improves the quality of the alloy products used. However, the total amount of the metal, utilized in these areas, is rather small.
Electrodeposition of tungsten-rhenium alloys from solutions after processing rhenium-tungsten-bearing wastes
Published in Gülhan Özbayoğlu, Çetin Hoşten, M. Ümit Atalay, Cahit Hiçyılmaz, A. İhsan Arol, Mineral Processing on the Verge of the 21st Century, 2017
L.Ya. Agapova, S.N. Aitekeyeva, E.I. Ponomareva, Z.S. Abisheva, T.N. Bukurov
The importance of rhenium and its alloys for industrial and academic progress is increasing continuously that was declared at the International Congress “Rhenium and Rhenium Alloys” in the USA, Orlando (Proc.Inter.Symp. 1997). Rhenium and its alloys are widely applied in radiotronics, instrument engineering, petroleum chemistry and other branches of industry. Rhenium-tungsten alloys possess the most valuable properties and are used for manufacturing high-temperature thermocouples.
Re, 75]
Published in Alina Kabata-Pendias, Barbara Szteke, Trace Elements in Abiotic and Biotic Environments, 2015
Alina Kabata-Pendias, Barbara Szteke
Rhenium is not an essential element, and the toxic effect occurs only at its high concentrations. Because its uptake by plants is limited, the animal and human tissues contain it in very small amounts. Therefore, negative consequences because of Recontent in agricultural production and human nutrition are not a reality, so its toxic effects are not important (Szabó 2009).
Equilibrium modeling in adsorption of Re and Mo ions from single and binary aqueous solutions on Dowex 21K resin
Published in Geosystem Engineering, 2018
Mohammad Bagher Fathi, Bahram Rezai, Eskandar Keshavarz Alamdari, Richard Diaz Alorro
Rhenium is considered as among one of the rarest elements in the Earth’s crust and is widely used in high-technology applications, i.e., metallurgy, petrochemical industry, aviation, medicine, defense, and chemical, due to its unique physical and chemical properties (Xiong et al., 2011). Rhenium does not occur naturally and no known mineable ore has been identified so far. Molybdenites and porphyry copper–molybdenum ores are typical primary sources of rhenium (Lou et al., 2013; Van Deventer, 2011). Separation of Re from aqueous solutions is usually difficult due to its low concentration and the complex coexistence of other metals ions, specifically Mo. Rhenium separation from molybdenum is critical and is a challenging task in hydrometallurgy owing to the similarities in their chemical properties.
Studying propagation of wave of metal foam rectangular plates with graded porosities resting on Kerr substrate in thermal environment via analytical method
Published in Waves in Random and Complex Media, 2022
One of the rarest elements in Earth's crust is Rhenium. Rhenium is a silvery-white metal with very great melting and boiling points and because of this fact, it can be used in various technological applications such as nuclear reactors, semiconductors, thermocouples, mass spectrometer filaments, cathode cups and grid heaters. Also, it can be added to other resistant metals as it amplifies the ductility, tensile and creep strengths and wear resistance of the alloys. Particularly, Rhenium is added to high-temperature super-alloys which are utilized to manufacture jet engine parts and another main application of it, is in platinum–rhenium catalysts and also Rhenium hexafluoride (ReF6) is utilized in the electronics industry for rhenium's depositing films [34–36].
IR laser ablation of high boiling elements (C, Mo, Ta, W and Re)
Published in Radiation Effects and Defects in Solids, 2021
Rhenium is used as an additive to tungsten- and molybdenum-based alloys to give useful properties. These alloys are used for oven filaments, lamps and X-ray machines. They can be also employed as electrical contact materials with high resistance to wear and withstand arc corrosion (switches for low and high voltages) (11). Rhenium is used as an important component in superalloys for blades in turbine engines for jet aircraft and industrial gas turbine engines submitted to continuum work at high temperature; it is also used in thermocouples which can measure temperatures above 2000 °C, and for electrical contacts which stand up well to electric arcs. Rhenium–molybdenum alloys are superconductors at a temperature of the order of 10 K (12).