Simple and Feasible Method for ⁶⁷Ga Production on CS-30 Cyclotron With High Purity

⁶⁷Ga is a classical single photon imaging nuclide, which also has therapeutic potential due to its simultaneous emission of auger electrons. At present, ⁶⁷Ga is mainly prepared by enrichment of Zn target. ⁶⁷Ga can also be obtained by ^natZn(p, xn)⁶⁷Ga nuclear reaction, but the existing separation methods and processes need to be further optimized. In this study, a simple and feasible method for the preparation of high radionuclidic purity ⁶⁷Ga from natural zinc target was studied. Zinc target with good quality was prepared by zinc sulfate system with target thickness ＞70 mg/cm². To determine the best separation scheme of Ga, the simulated separation experiment of non-radioactive elements using 60% tributyl phosphate(TBP) resin was carried out. The distribution coefficients of Ga³⁺, Zn²⁺, Cu²⁺, Ni²⁺ and Co²⁺ ions in w=60% TBP resin under the action of 0.05, 0.10, 0.50, 1.00, 2.00, 4.00, 6.00 and 8.00 mol/L HCl were determined. We found that NH₄Cl solution has good elution performance and can elute the adsorbed gallium. After eluting with 6.00 mol/L HCl, then eluted with 0.10, 0.30, 0.50, 0.75, 1.00 mol/L NH₄Cl solution. The recovery of Ga was calculated respectively. According to the actual situation, the simulated solution was prepared and verified according to the experimental conditions obtained. 6.00 mol/L HCl and 0.50 mol/L NH₄Cl were selected as the eluent. The results show that 60% TBP extraction resin has good separation effect. In order to verify the effectiveness of our separation method, a simulation separation experiment with trace amounts of radioactive Ga is conducted. The results of ⁶⁸Ga tracer experiments are as good as those of non-radioactive experiments. The natural zinc target prepared by electroplating was bombarded with a beam of 21 MeV protons at 50 μA on the CS-30 cyclotron. The separation and purification process of high radionuclidic purity ⁶⁷Ga from irradiated zinc target solution was established based on TBP extraction resin. According to the isotopic composition of zinc target material, the presence of trace amounts of ⁶⁴Ga, ⁶⁵Ga, ⁶⁶Ga, ⁶⁷Ga, ⁶⁸Ga is estimated. However, after 5 days of decay, no short half-life nuclides(⁶⁴Ga, ⁶⁵Ga, ⁶⁸Ga) have appeared, but a trace amount of ⁶⁶Ga is still present in the product. The separation process is simple and efficient. The whole separation process can be completed within 2 hours. The radioactive recovery rate is greater than 90%. The radionuclidic purity is more than 99.9%. The yield of ⁶⁷Ga obtained by ^natZn(p, xn)⁶⁷Ga reaction is 13 MBq/(μA•h). This method also has reference value for the preparation of ⁶⁸Ga by accelerator.