Production of high-purity26Al

²⁶Al is a positron emitting radioisotope of aluminium and has a half-life of 7.16×10⁵y. In addition to annihilation -rays of 511 keV, there are three high energy -rays 1129 (2.4%), 1809 (99.73%) and 2938 (0.27%) keV.²⁶Al is the only radioisotope of aluminium available for radiochemical applications, the half-lives of the other aluminium isotopes are seconds and minutes. The usage of²⁶Al is very important in the investigations of the metabolism of Al in human body (for example in Alzheimer disease studies) or as a tracer in radiochemical studies. But²⁶Al is such a long-lived isotope that the task of producing it in tangible amounts is a very difficult one.