Thermal conversion in air of rare-earth fluorides to rare-earth oxyfluorides and rare-earth oxides

被引：8

作者：

Chong, Saehwa ^{[1
]}

Riley, Brian J. ^{[1
]}

机构：

[1] Pacific Northwest Natl Lab, Richland, WA 99354 USA

来源：

JOURNAL OF NUCLEAR MATERIALS | 2022年 / 561卷

关键词：

Oxyfluoride; Molten salt reactor; Fluoride salt wastes; R(N)O(2N-2) HOMOLOGOUS SERIES; OXIDATIVE PRECIPITATION; CRYSTAL-STRUCTURE; MOLTEN-SALT; WASTE SALT; DIFFRACTION; CHLORIDES; CERIUM; STATE;

D O I：

10.1016/j.jnucmat.2022.153538

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The goal of this study was to evaluate a potential method to convert rare-earth (RE) fluorides to oxides through thermal conversion in air. The RE elements, which are common neutron poisons, could potentially be removed from fluoride-based molten salt reactors via precipitation through fluoride-tooxyfluoride or fluoride-to-oxide conversion mechanisms. In this study, the phase transformations of seven different REF3 com pounds (RE = La, Ce, Pr, Nd, Tm, Yb, and Lu) at temperatures ranging from 400 to 1400 degrees C in air were investigated with X-ray diffraction. The LaF3, PrF3, NdF3, TmF3, YbF3, and LuF3 compounds transformed to oxyfluorides first and then to oxides, whereas CeF3 transformed directly to an oxide. A waste form option for the resulting REOx products is a lanthanide aluminoborosilicate (LABS) glass, which was demonstrated in this paper by converting NdF3 to Nd2O3 and immobilizing the Nd2O3 at 60 mass% in a LABS glass.(c) 2022 Elsevier B.V. All rights reserved.

引用

页数：9

共 49 条

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