Production of 28Mg by bombardment of natCl with 200Â MeV protons: Proof-of-concept study for a stacked LiCl target

A stacked target consisting of ten Al-encapsulated LiCl discs, for producing 28Mg via the natCl(p,X)28Mg process in the energy region 50-200 MeV, is described. This target was irradiated with a 200 MeV beam at an intensity of 100 nA, providing information on both yield and outscattering losses. Results of a Monte Carlo modelling of the beam and target, by means of the code MCNPX, are also presented. Similar Al-encapsulated LiCl discs were individually irradiated with 66 MeV proton beams of 65 and 90 μA, respectively, to study their behaviour under high-intensity bombardment. Once removed from the Al encapsulation, the 28Mg can be separated from the LiCl target material efficiently, using a 12.5 cm x 1 cm2 column containing Purolite S950 chelating resin. The eluate contains 7Be but no other measurable radio-contaminants. The removal of the 7Be contaminant is performed by cation exchange chromatography in malate media, with 28Mg being retained by the resin and 7Be eluted.