Optimization of extraction and stripping methods in analysis of zirconium isotope as burn-up monitoring

Optimized extraction and stripping process parameters have been obtained both for standard Zr separation and Zr analysis in fresh fuel. The research aims to prepare separation method of Zr in both fresh and irradiated fuel. It is necessary since Zr is one of isotope for burn-up monitoring which has short half life. Separation of Zr was carried out by extraction method followed by stripping. The result of Zr separation by extraction process, Zr in the organic phase was stripped using H₂SO₄. The extraction process was carried out in various condition, i.e. time, acidity (HNO₃), and TBP (Tri Butyl Phosphate)/kerosene ratio variation, while the stripping process was carried out with time and acidity (H₂SO₄) variation. The extraction and stripping results were analyzed by UV-Vis spectrometry using arsenazo III complexing agent to obtain Zr content. The optimum extraction condition was found to be at extraction time of 40-50 minutes (distribution coefficient of 0.85 and efficiency of 45 %) in HNO₃ 5M and TBP/kerosene ratio of 50:50 % volume, while the optimum condition for stripping process was at H₂SO₄ 2M acidity for 40 minutes. These optimized parameters in the extraction and stripping process were used as analysis of Zr in UZr 6% alloy, where was obtained separation recovery of Zr was 91,840 %. The optimum parameters of extraction and stripping method for separation of Zr in UZr fuel was used in the separation of Zr from other fission products in irradiated fuel. (author)