Preparation of 26Al, 59Ni, 44Ti, 53Mn and 60Fe from a proton irradiated copper beam dump

Abstract

The station for pions cancer therapy was operated at PSI from 1980 to 1992. After a cooling time of 12 years it's made of copper beam dump was cut and samples were taken for analytical purposes. The sampling collected about 500 g of high active copper chips that can be used for separation of exotic radionuclides. The analyses by gamma spectrometry, LSC and AMS showed main nuclides present to be 60 Ti with a daughter nuclide 44 Sc. In the frame of ERAWAST project a procedure combining selective precipitation and ion exchange for the separation of the rare radionuclides from the copper beam dump was developed. The proposed separation procedure is easy for remote controlled implementation in a hot cell. The ion exchange separation of Ni, Al, Mg, Ti and Fe was complete and high decontamination factors for copper and cobalt were achieved. Based on the developed procedure a remotely controlled system for separation of exotic radionuclides from the copper chips was set up. The full scale system was installed in a hot cell where high activity levels can be handled. In order to evaluate the reliability and functionality of the system extensive tests have been done. During the test period 13.86 g in total of the proton irradiated copper beam dump were processed for separation of 26 Al, 59 Ni, 53 Mn, 44 Ti and 60 Fe. The results showed that the system was operational and the radionuclide separation was selective with high chemical yield. The procedure manages as well the generated liquid wastes containing high level of 60 Co activity.

Analysis of long-lived radionuclides produced by proton irradiation in lead targets – γ -measurements

“…Hence, chemical techniques have to be applied in order to separate interfering nuclides. Several examples to separate 44 Ti/ 44 Sc from radioactive waste are described in literature [10,23,24]. This task will be faced in future work.…”

Emission probability of the 66.7 keV γ transition in the decay of Tm171

“…the abundance of ( 171 Tm + 171 Yb) in the used solution, was measured 8 times by HR-ICP-MS using an Element 2, Thermo-Fischer Scientific, Bremen, Germany, operated in low resolution mode and wet plasma conditions. A secondary calibration source was prepared from a purified stock solution 44 Ti/ 44 Sc available from earlier experiments [11]. An aliquot of this stock solution was diluted with MilliQ water to yield a solution containing approx.…”

“…A secondary calibration source was prepared from a purified stock solution 44 Ti/ 44 Sc available from earlier experiments [11]. An aliquot of this stock solution was diluted with MilliQ water to yield a solution containing approx.…”

Neutron capture cross section of Mn53 from irradiation with cold and reactor neutrons

“…The purified 53 Mn fraction [20] in the form of an acidic chloride solution was evaporated to dryness and redissolved in approx. 0.5 mL 1 M HCl.…”