Endang Susiantini, Ary Purnomo
Reduction Of Hf Concentration By Using Continuous Annular Chromatography (CAC). Concentration of Hf in Zr to be used in the control rods in nuclear reactors was less than 100 ppm. Various methods for obtaining Hf concentration as small as possible have been carried out, one of them was CAC. The purpose of this research was to find the optimum conditions of rotation speed, concentration and processing time of elution using H2SO4 in order to obtain the minimum concentration of Hf in Zr. The apparatus used for the reduction of Hf concentration was CAC equipped with data acquisition control. The size of the annular length is 50 cm, outer diameter of annular pipe is 19.5 cm, inner diameter is annular pipe is 18 cm. Feed of Zr-sulfate obtained from the processing product of zircon sand having concentration of 100 g/l containing 5032.745 ppm or 0.532% Hf. One liter of feed was flown at a feed nozzle from the top of the annulus with speed of (3-5) ml/min and at the same time the elution solution was flown at a flowrate of 3 ml/minutes for 4 hours. Elution was carried out stepwisely with 2M H2SO4 then subsequently followed by a higher concentration of 4M H2SO4 for 4 hours. Analysis of the elution results of Zr was done titrimetrically whereas Hf by Neutron Activation Analysis (NAA). The results obtained indicate the rotation speed of 20 rpm, elution by using 4MH2SO4 at the fourth hour producing concentration of Hf/Zr less than 500 ppm. © 2015, Sphinx Knowledge House. All rights reserved.
Center for Accelerator Science and Technology, Yogyakarta, Indonesia; State Yogyakarta University, Yogyakarta, Indonesia
