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Synthesis Of Noble MetalsAs Synthesis of noble metalls one calls the realization of the old dream of alchimests, to produce noble metalls in a synthetic way. The synthesis of noble metalls is only possible with methods of nuclear physics, either by nuclear reactors or by particle accelerators. Particle accelerators require huge amounts of energy, while nuclear reactors produce energy, so for the synthesis of noble metals only methods, which can be done in a nuclear reactor, are from interest. Synthesis of Rhodium and Ruthenium Rhodium and Ruthenium are produced at nuclear fission with amounts of a few percent of the whole fission products. The isotopes of these elements with the longest duration of half-life, which are generated by nuclear fission (isotopes of rhodium and uthenium, which decay by K+-decay or positron decay are not a result of nuclear fission) have half-life times from 45 days (for rhodium) and 373.59 days (for ruthenium), so that their extracction from burned-out nuclear fuel is principially possible, although they have to be checked very carefully for radioactivity, before leaving the controll range. Until now in no facility for recycling nuclear fuels rhodium and ruthenium are extracted. In future times this may change and so nuclear waste could be in future under some circumstances from economical interest. Palladium is also produced by nuclear fission in amounts of some percents. In opposite to rhodium and ruthenium, the so produced palladium contains a radioactive isotope with a long-time half-life time, Pd 107 with a half-life time of 6.5 million years, so palladium produced in this way is radioactive and radiates with an intensity, which is more than 100 times greater than that of uranium, if this isotope is not seperated from the other palladium isotopes, which is very expensive. Silver Silver is produced as result of nuclear fission in small amounts (approximately 0.1 %). Because of this, small lots an extraction of silver from high radioactive fission products would be very unecconomically, because the price for silver is much less then for rhodium and ruthenium (price per kilogram: silver: 300 €, rhodium and ruthenium: 300000 €) These noble metals are not produced by nuclear fission. A production by long time irradiation of tungsten in a reactor would be thinkable. Tungsten indeed has some properties of these metalls as high chemical resistance and a high melting point, so transforming tungsten in these metals seems not to be an attractive idea. Gold Gold is not a result of nuclear fission. Methods of making gold in an artifical way are found under gold synthesis. From these elements only a few atoms can be produced in particle accelerators, which decay very rapidly.
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