Transmutation

The term Transmutation means in chemistry and nuclear physics the conversion of one chemical element into another one.

Transmutations take place under extreme conditions in stars like the sun (e.g. nuclear fusion) and can be observed in natural radioactive decay. In principle, they can also be controlled by man. For example in nuclear fission processes (nuclear power plants, atomic and hydrogen bomb explosions). By neutron bombardment or bombardment with charged particles may lead to transmutations, e.g. in atomic reactors. Since the 1940s Plutonium 239 and Uranium 233 are won from Uranium 238 and Thorium 232 industrially, to build atomic bombs.

In theory transmutations might have practical appliance for the creation of gold or other precious metals, but costs and effort are too high and therefore not commercially attractive. Transmutation facilities could be used to dispose nuclear waste, but as of 2011 just small experimental facilities exist. A european research facility(MYRRHA project) is planned in Mol, Belgium and might be built by 2020. The necessary time of final storage of the remaining waste should be reduzed from 500,000 years to 500.

Origin

Originally, the term was used by Alchemists, who believed for centuries to be able to create gold from other elements just through normal chemical reactions or magical acts. Such hypotheses were discussed even in the 17th, 18th and 19th centuries.

Use in pseudoscience

Despite the lack of evidence, disappointing experiments and against established knowledge of chemistry, the rumour that transmutations, for exampled to provide energy, can be affected with little effort holds to this day. To distinguish such hypotheses from actually possible transmutations under extreme conditions the term CANR(Chemically Assisted Nuclear Reactions) was introduced. An example for such considerations are speculations about alleged successful experiments with cold fusion, for instance by electrolysis. In most cases this is put in the context of a conspiracy theory, that powerful interest groups prevent or cover up such experiments. Such speculations are for example spread by supporters of the U.S. citizen Lyndon LaRouche.

A special role is played by hypotheses about possible biological transmutations in biology, that have been discussed since the 17th Century and find sporadic supporters even today.

Versions of this article in other languages

• Deutsch: Transmutation

Literature

• Mikhail Kh. Khankhasayev: Nuclear methods for transmutation of nuclear waste - problems, perspectives, cooperative research. World Scientific Publ., 1997, ISBN 981-02-3011-7.