中文摘要：

CaO-NaCl-CaCl2焙烧包头混合型稀土精矿的产物经脱磷处理后,矿物中的物相主要为稀土氧化物和氟化钙。以较低浓度AlCl3作为助浸剂用HCl溶液浸出矿物,利用低浓度的Al3＋与氟形成氟铝配合物,有效地帮助难溶物相氟化钙浸出,同时避免浸出过程中氟离子与稀土形成氟化稀土沉淀而造成损失。结果表明：盐酸浓度为3 mol.L-1,Al3＋浓度为0.25 mol.L-1,温度为60℃,液固比为10∶1,浸出时间为60min,搅拌速度为200 r.min-1时,稀土氧化物的浸出率为70.8%,氟化钙的浸出率为55.8%。五级逆流浸出后,RE2O3的浸出率为99.6%,CaF2的浸出率达到98.5%。

英文摘要：

The Baotou mixed rare earths concentrate was decomposed by CaO-NaCl-CaCl2,and the rare earths oxide and CaF2 were the main phase in decomposed mixed rare earths concentrate phosphors.In this paper,low concentration AlCl3 was used as an assisted leaching agent in process of minerals leached by HCl.The Al3＋coordinated with F-to increase the leaching ratio of CaF2 and inhibited the rare earths loss as fluoridation precipitation.The experimental results showed that the leaching ratio of RE2O3 and CaF2 was up to 70.8% and 55.8%,respectively at the optimization parameters： HCl concentration 3 mol·L-1,Al3＋ concentration 0.5 mol·L-1,liquid to solid 10∶1,stirring speed 200 r·min-1,at 60 ℃ for 60 min,and the leaching ratio of RE2O3 and CaF2 was to 99.62% and 98.56%,respectively when quinternary contraflow leaching at the same parameters.