放射性铌铁精矿中铀钍的脱除及分离

Removal and Separation of Uranium and Thorium from Radioactive Nb-Fe Concentrate

通过对国内某企业进口放射性铌铁精矿进行工艺矿物学分析,确定该精矿的主要矿相为烧绿石,同时伴生钛铁矿和白云母,矿石中放射性元素U和Th的含量分别为0.27%和1.03%。针对该铌铁精矿,探索H_(2) SO_(4)-Fe(Ⅲ)、H_(2)SO_(4)-HF-H_(2)O_(2)、H_(2)SO_(4)-HF、H_(2)SO_(4)-HF-H_(2)O_(2)-(NH_(4))_(2)CO_(3)体系中U和Th的浸出及分离效果,最终确定H_(2) SO_(4)-HF-H_(2)O_(2)-(NH_(4))_(2)CO_(3)多段浸出工艺能有效实现U和Th的脱除与分离。U、Th的脱除率分别为100%和80%。基于研究提出了铌铁精矿U、Th脱除及分离工艺流程。

Through the process mineralogy analysis of the radioactive Nb-Fe concentrate imported by a domestic enterprise,the main mineral phase of the concentrate is pyrochlore,associated with ilmenite and muscovite.The contents of radioactive elements U and Th in the ore are 0.27% and 1.03% respectively.For this Nb-Fe concentrate,the leaching and separation effects of U and Th in H_(2)SO_(4)-Fe(Ⅲ),H_(2)SO_(4)-HF,H_(2)SO_(4)-HF-H_(2)O_(2),and H_(2)SO_(4)-HF-H_(2)O_(2)-(NH 4)2CO_(3) systems were explored.Finally,it is determined that H_(2)SO_(4)-HF-H_(2)O_(2)-(NH_(4))2CO_(3) multi-stage leaching process can effectively remove and separate U and Th.The removal efficiency of U and Th is 100% and 80% respectively.Based on the research,the removal and separation process of U and Th from Nb-Fe concentrate is proposed.