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History
History
The hafnium seal of the Faculty of Science of the University of Copenhagen
The hafnium seal of the Faculty of Science of the University of Copenhagen
The 1869 periodic table by Mendeleev had implicitly predicted the existence of a
heavier analog of titanium and zirconium, but in 1871 Mendeleev placed lanthanum
in that spot.
The existance of a gap in the periodic table for an as-yet undiscovered element
72 was predicted by Henry Moseley in 1914. Hafnium (Latin Hafnia for
"Copenhagen", the home town of Niels Bohr) was discovered by Dirk Coster and
Georg von Hevesy in 1923 in Copenhagen, Denmark, validating the original 1869
prediction of Mendeleev. Soon after, the new element was predicted to be
associated with zirconium by using the Bohr theory and was finally found in
zircon through X-ray spectroscope analysis in Norway.
It was separated from zirconium through repeated recrystallization of double
ammonium or potassium fluorides by Jantzen and von Hevesey. Metallic hafnium was
first prepared by Anton Eduard van Arkel and Jan Hendrik de Boer by passing
hafnium tetraiodide vapor over a heated tungsten filament. This process for
differential purification of Zr and Hf is still in use today.
The Faculty of Science of the University of Copenhagen uses in its seal a
stylized image of hafnium.
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