复杂稀有金属矿综合利用新工艺

研究一种从复杂稀有金属矿中综合回收稀土、铌、钛的新工艺。按6∶5的酸矿质量比添加浓硫酸混匀后在400℃酸化,酸化渣浸出后,浸出液按1∶1的体积比加水在100℃水解60min得到水解沉淀,浸出渣采用强磁选分离得到磁性物及非磁性物。将水解沉淀与磁性物混匀在1 800℃还原熔炼,获得Nb2O5含量22.38%、铁品位52.32%的铌铁合金和TiO2含量35.12%的钛渣,铌、钛回收率分别为66.89%和50.38%。水解液在通入空气的条件下用氨水调节至pH=3进行固液分离,按理论量1.2倍添加草酸沉淀稀土,最后将该稀土沉淀在950℃煅烧60min,可得到REO含量92.4%的稀土氧化物,稀土总回收率71.32%。

New Comprehensive Utilization Process for Complex Rare-Metal Ore

A new process of rare earth,niobium and titanium recovered from complex rare-metal ore was studied.The ore was acidized at 400 ℃ with the mass ratio of concentrated sulfuric acid and raw ore of 6∶5.The solution,obtained from the acidification slag leaching process,was hydrolyzed at 100 ℃ for 60 min with the addition of water according to the volume ratio of 1∶1,and the hydrolysis precipitation was obtained.The leached residue was treated by strong magnetic separation to obtain the magnetic and nonmagnetic materials.The mixture of the hydrolysis precipitation and magnetic materials were reduction smelted at 1 800 ℃ to obtain the ferrocolumbium with 22.38% Nb2O5 and 52.32% TFe and the titanium slag with 35.12% TiO2,and the recovery of niobium and titanium was 66.89% and 50.38%,respectively.The rare earth oxide products with REO content of 92.4% could be obtained with the total recovery of rare earth of 71.32% when the hydrolysis solution was adjusted to pH value of 3 with the addition of ammonia water in oxidizing atmosphere and solid-liquid separation,oxalic acid was added according to 1.2 times of the rare earth theory dosage to the filtrate,and the oxalic acid rare earth was roasted at 950 ℃ for 60 min.