Target Chemistry of Zirconium and Yttrium; Isolation of Zr89 in Pure State

Abstract

Radioactive Zr89 obtained by bombardment of Y2O3 with deuterons, was separated without addition of stable zirconium in quantities ∼10−10 gram. Oxychloride solutions of Zr89 mixed with inactive Zr were used for coagulation studies in the concentration range 1.5×10−4−1.5×10−11 gA/l. It was found that the fraction coagulated increased with dilution under the constant conditions used (pH−4.0; NaCl−2.5×10−2N; T−25°), to 2.7×10−6 gA/l. The log-log plot of zirconium concentration (C) in solution against coagulated part (c) closely approaches a straight line with exponent n=1.50 and k=490. At 1.5×10−6 gA/l and lower concentrations the coagulated fraction reaches a maximum and becomes constant, k=C/c=.45. Within the range studied salt increases coagulation of zirconium above 10−5 gA/l; but below 10−6 gA/l the salt effect is reversed. Increase in pH results in increase in the fraction coagulated (r) in all concentrations studied. At a minute concentration r=(pH—K)/m, K being 1.85 with NaCl, 0.05N and 1.58 with NaCl, 0.005N and m being 3.15. The separation of Zr89 in minute quantities without addition of stable zirconium is plausible if a Nernst distribution of zirconium between coagulated part and solution is postulated. The concept of the solubility of the hydrous oxide of zirconium as a constant quantity remaining in solution under specified conditions was not verified.