微波辅助氟碳铈矿固氟焙烧实验研究

Experimental Study on Microwave Assisted Roasting for Fluorine-absorption of Bastnaesite

针对氟碳铈矿分解过程中的固氟问题,采用＂微波辅助氟碳铈矿固氟焙烧＂工艺,借助XRD、SEM、EDS以及化学检测等手段,研究了微波场中活性炭辅助加热的升温特性和焙烧条件对氟碳铈矿分解率的影响规律,结果表明,随着配碳量的增加,平均升温速率提高;最佳焙烧条件为：焙烧温度700℃,保温时间20 min,Ca O加入量15%,Ca Cl2-Na Cl加入量8%;焙烧矿中稀土以氧化物的形式存在、氟以Ca F2的形式存在;最佳焙烧条件下氟碳铈矿的分解率为95.88%,固氟率为97.57%。本工艺快速高效,为后续稀土与氟的分离创造了条件。

In this paper,in order to solve the problem of fluorine-absorption in separation of RE from fluorine in decomposition of bastnaesite,influence of heating characteristics and roasting conditions on bastnaesite decomposition rate in microwave field was studied by using the process of ＂microwave assisted fluorocarbine roasting＂and by means of XRD,SEM,EDS and chemical analysis.The results show that the average heating rate increased with the carbon addition rising,and the optimum roasting condition was roasting temperature 700 ℃,heat preservation time 20 min,Ca O addition 12% and Ca Cl2-Na Cl addition 8%. In the decomposition products,RE existed in rare earth oxides and fluorine existed in the form of Ca F2,and decomposition rate of bastnaesite reached to 95. 88%,fixed fluorine rate reached to 97. 57% at the optimum roasting condition. This process is rapid and efficient,providing conditions for subsequent separation of rare earth and fluorine.