低品位难处理钽铌矿中铌的浸出试验研究  

Leaching of Niobium from Low-Grade Refractory Tantalum-Niobium Bearing Minerals

作　　者：武彪[1] 尚鹤[1] 温建康[1] 

机构地区：[1]北京有色金属研究总院生物冶金国家工程实验室,北京100088

出　　处：《稀有金属》2013年第5期791-797,共7页Chinese Journal of Rare Metals

基　　金：国家科技部科技支撑项目(2012BAB10B00)资助

摘　　要：目前世界上大部分铌矿矿山采用硫酸-氢氟酸分解法湿法冶金处理工艺,但氢氟酸的毒性高、腐蚀性强,对设备材质要求高,而且成本高,不适宜处理低品位矿石。针对我国攀西地区某低品位铌矿开展了工艺矿物学和纯硫酸体系酸化焙烧-浸出工艺研究,考察了不同焙烧时间、用酸量等对铌浸出率的影响。研究结果表明:该矿石含铌矿物主要由褐钇铌矿、复稀金矿和铌铁金红石组成,N2O5含量0.034%,嵌布粒度细,比较分散,属于低品位极难处理铌矿。铌属于难溶金属,在低温(温度低于100℃)下,采用强酸、强碱浸出,铌浸出率低于30%,无法得到有效回收。添加H2O2与水合铌矿物形成酸可溶的配合物,有效提高了铌浸出率。获得最佳的工艺参数为:在磨矿细度为-74μm占80%,硫酸化焙烧的温度为250℃,硫酸用量占原矿质量比为75%,添加H2O2用量占原矿质量比为70%,焙烧时间2 h;浸出温度90℃,液固比4∶1,酸矿比为3∶1,浸出时间2 h的条件下,铌浸出率达到81%。Hydrofluoric-sulfur acid dissolution technology was widely used in most of niobium minerals processing. However the hydrofluoric acid was toxicity, corrosion resistance, high requirements for equipment, and high cost, it was not suitable for processing low-grade ore. The mineralogy and sulfur acidification roast-leaching of the low-grade niobium ores from some mine in the southwest of China were studied. And the influence of different roasting time and acid content on the leaching rate of Nb was discussed. The results showed that the niobium bearing minerals were mainly composed of fergusonite, polycrase and ilmenorutile, with low grade（ N2O5 con- tent was 0.034% ）, disseminated fine grain size and scattered distribution, it was the low-grade refractory niobium ore. Niobium be- longed to insoluble metal, at low temperature （temperature lower than 100 ℃）, the niobium leaching rate was less than 30% under the acid and alkali conditions, it could not be effectively recovered. However, H2O2 and hydrated niobium mineral could form the acid- soluble complexes, adding H2O2 effectively improved the leaching rate of niobium. The ore was roasted under the conditions of grinding fineness -74 μm 80%, roasting temperature 250 ℃, 75% mass ratio of acid to ore after 2 h, then the residue leached under condi- tions of liquid-solid ratio 4： 1, mass ratio of acid to ore 3： 1, temperature 90 ℃ and adding H2O2 to ore mass ratio of 70% after reten- tion 2 h, the optimal niobium leaching rate was 81%.

关 键 词：低品位难处理铌矿 酸化焙烧 硫酸浸出 浸出率 

分 类 号：TF111.3[冶金工程—冶金物理化学]