Preparation and characterization of powellite ceramics Ca1-xLix/2Cex/2MoO4 (0 ≤ x ≤ 1) for Mo-rich HLW condition |
| |
| Affiliation: | 1. Guangxi Universities Key Laboratory of Non-Ferrous Metal Oxide Electronic Functional Materials and Devices, Guilin University of Technology, Guilin, 541004, China;2. Materials Research Institute, Pennsylvania State University, University Park, State College, PA, 168001, USA;3. Institute for Superconducting and Electronic Materials, University of Wollongong, Wollongong, New South Wales, NSW 2500, Australia;4. Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education and International Center for Dielectric Research, Xi’an Jiaotong University, Xi’an, 710049, China;5. Thin Film and Optical Manufacturing Technology Laboratory, Key Laboratory of Ministry of Education, Xi’an Technological University, Xi’an 710032, China;1. Department of Physics, R.T.M. Nagpur University, Nagpur, 440033, India;2. Department of Applied Physics, O.P. Jindal University, Punjipathra, Raigarh, 496109, India |
| |
| Abstract: | Powellite ceramic represent one candidate to immobilize minor actinides and Mo from reprocessed UMo nuclear fuel. In this work, the Ca1-xLix/2Cex/2MoO4 (0 ≤ x ≤ 1) series is prepared via a solid-state reaction using Ce3+ as trivalent minor actinide (Am3+) surrogate, with structure/microstructure characterized by XRD, XPS, HRTEM, and SEM as well. The Ca1-xLix/2Cex/2MoO4 (0 ≤ x ≤ 1) compositions crystallize in tetragonal and are isostructural with scheelite. Rietveld refinements show that Ce3+ and Li+ simultaneously enter into the eight-fold coordinated Ca site of powellite crystal. The chemical durability of powellite phases is evaluated by the ASTM C1285-14 product consistency test method B. The leaching behaviours of Ce and Mo are accordance with the interfacial dissolution-reprecipitation mechanism. For all the Ca1-xLix/2Cex/2MoO4 (0 ≤ x ≤ 1) ceramics, 7-days NLCe and NLMo are found to be in the order of 10?3-10?5 g·m?2 and 10?2-10?4 g·m?2 respectively, which exhibit the great retention of Ce and Mo. Interestingly, the values of 7-days NLCe and NLMo are predominantly controlled by the distortion of MoO4 tetrahedra and disordered arrangements of Ce3+ and Li+. Thus, our initial understanding on the structure and chemical durability relation will provide insight to design new waste forms for the Mo-rich HLW condition. |
| |
| Keywords: | HLW Powellite Immobilization Leaching |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
