活化分解氟碳铈精矿对钙化转型提取稀土的影响

Activating Decomposition of Bastnaesite Concentrate to Extracting Rare Earth with Calcification Transition Process

采用活化预处理-加压钙化处理氟碳铈精矿新工艺,研究了活化温度、活化时间对精矿分解、氟元素损失的影响,及不同温度活化分解精矿钙化转型后对稀土浸出率的影响,并计算了活化前后精矿钙化转型过程中动力学参数。结果表明:氟碳铈精矿经过活化分解更利于钙化转型过程的进行,稀土总浸出率由27.81%提高到70.76%;480℃温度下活化60 min,精矿基本分解完全,氟损失率为3.24%;通过计算得出氟碳铈精矿钙化转型过程为化学反应控制,而活化后精矿的钙化转型过程为扩散过程控制。

The decomposed process of bastnaesite concentrate was studied. The relationship among decomposition, loss rate of fluorite, leaching rate of rare earth, activation temperature and time was investigated. The kinetic pa- rameters of the activated bastnaesite and the unaetivated bastnaesite in the calcification transition process were cal- culated. The activating affected the behavior of rare earth in the calcification transition process and leaching rate of total rare earth increased from 27.81% to 70.76%. And bastnaesite concentrate was decomposed completely at 480 ℃ for 60 min, while the loss rate of fluorine was 3.24%. It indicated that the calcification transition process for activated bastnaesite was controlled by diffusion process of reactant.