Scholarlink

<p>Langbeinite is proposed as a promising host matrix for radioactive wastes, but no structures incorporating actinides have been reported yet. In this work, a series of single crystals of Cs<sub>2</sub>U<sup>Ⅳ</sup>Ln(PO<sub>4</sub>)<sub>3</sub> (Ln = Ce – Nd and Sm – Lu), the first reported langbeinite-type structure incorporating actinides (U<sup>IV</sup>) which crystallizes in the cubic space group <i>P</i>2<sub>1</sub>3, have been successfully prepared by optimizing the high-temperature molten salt method. Their 3D frameworks are characterized by a typical langbeinite structure with U/Ln co-occupying six-coordinated octahedra and Cs cations filling closed large-sized cavities. The compounds exhibit high thermal stability up to 1200 °C under N<sub>2</sub> and show outstanding leaching resistance, with the leaching rates of U and Nd at 10<sup>−8</sup> g·m<sup>−2</sup>·d<sup>−1</sup> and Cs 10<sup>−3</sup> g·m<sup>−2</sup>·d<sup>−1</sup>. This study highlights the potential of langbeinite-type structures for effectively immobilizing both tetravalent and trivalent actinides as promising waste forms.</p><p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Incorporation of uranium to the langbeinite family in Cs2UⅣLn(PO4)3 actinide waste forms

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2025年11月27日

查看全文
  • Yu Wang,
  • Lanxin Li,
  • Tao Bo,
  • Zhenyu Han,
  • Yongliang Tang,
  • Wenwen Lin,
  • Meng Zhang,
  • Jie Qiu,
  • Lei Zhang

摘要

Langbeinite is proposed as a promising host matrix for radioactive wastes, but no structures incorporating actinides have been reported yet. In this work, a series of single crystals of Cs2UⅣLn(PO4)3 (Ln = Ce – Nd and Sm – Lu), the first reported langbeinite-type structure incorporating actinides (UIV) which crystallizes in the cubic space group P213, have been successfully prepared by optimizing the high-temperature molten salt method. Their 3D frameworks are characterized by a typical langbeinite structure with U/Ln co-occupying six-coordinated octahedra and Cs cations filling closed large-sized cavities. The compounds exhibit high thermal stability up to 1200 °C under N2 and show outstanding leaching resistance, with the leaching rates of U and Nd at 10−8 g·m−2·d−1 and Cs 10−3 g·m−2·d−1. This study highlights the potential of langbeinite-type structures for effectively immobilizing both tetravalent and trivalent actinides as promising waste forms.