In order to investigate the anti-leaching capability of pyrochlore Gd2Zr2O7 immobilized An3＋, trivalent neodymium was used as the simulacrums for radioactive wastes with trivalence, Gd2-xNdxZr2O7（0.0 ≤ x≤2.0） ser...In order to investigate the anti-leaching capability of pyrochlore Gd2Zr2O7 immobilized An3＋, trivalent neodymium was used as the simulacrums for radioactive wastes with trivalence, Gd2-xNdxZr2O7（0.0 ≤ x≤2.0） series samples were successfully synthesized by high temperature solid reaction and using Gd2O3, ZrO2 powders as starting materials. The experiments of long-term chemical stability were conducted in synthetic seawater at 40 and 70 ℃. The XRD diffractive data and extraction ratio of as-received samples were collected with the help of X-ray diffraction （XRD） instrument and inductively coupled plasma mass spectrometry （ICP- Mass）. The results indicate that the phases of as-received compounds keep the single phase of pyrochlore. The extraction ratio of Gd3＋, Zr4＋ and Nd3＋ in waste forms is increasing with the increase of immersion time in synthetic seawater. The extraction ratio of waste forms at 70 ℃ is higher than at 40 ℃. The highest extraction ratio of Gd3＋, Zr4＋ and Nd3＋ after 42 days is near 0.025 8, 0.003 8 and 0.045 2 μg.mL-1, respectively.展开更多
基金Funded Partly by the Key Project of National High Technology Research and Development Program(863 Program)(No.2009AA050703)the National Natural Science Youth Foundation of China(Nos.41302028,21007052)+1 种基金the Sichuan Province Science and Technology Support Program(No.2011GZ0252)the Joint Laboratory for Extreme Conditions Matter Properties,Southwest University Science and Technology and Research Center of Laser Fusion,China Academy of Engineering Physics(No.12zxjk04)
文摘In order to investigate the anti-leaching capability of pyrochlore Gd2Zr2O7 immobilized An3＋, trivalent neodymium was used as the simulacrums for radioactive wastes with trivalence, Gd2-xNdxZr2O7（0.0 ≤ x≤2.0） series samples were successfully synthesized by high temperature solid reaction and using Gd2O3, ZrO2 powders as starting materials. The experiments of long-term chemical stability were conducted in synthetic seawater at 40 and 70 ℃. The XRD diffractive data and extraction ratio of as-received samples were collected with the help of X-ray diffraction （XRD） instrument and inductively coupled plasma mass spectrometry （ICP- Mass）. The results indicate that the phases of as-received compounds keep the single phase of pyrochlore. The extraction ratio of Gd3＋, Zr4＋ and Nd3＋ in waste forms is increasing with the increase of immersion time in synthetic seawater. The extraction ratio of waste forms at 70 ℃ is higher than at 40 ℃. The highest extraction ratio of Gd3＋, Zr4＋ and Nd3＋ after 42 days is near 0.025 8, 0.003 8 and 0.045 2 μg.mL-1, respectively.
