中文摘要：

对从含钽铌废渣中综合回收钽、铌的新工艺进行了研究。开发了低碱分解-水浸、稀酸预处理、氢氟酸转型浸出的湿法冶金工艺路线,通过实验确定了最佳工艺条件。其中低碱分解-水浸工艺条件为：碱渣质量比0.6∶1.0、反应温度800℃、反应时间1 h,添加剂Na Cl添加量为渣量的12%,水浸温度90℃,液固比6∶1,时间0.5 h。低碱分解过程中钽和铌的转化率分别为92.3%和98.2%。稀酸预处理后大部分杂质被脱除,钽、铌相对于原渣富集近5倍。转型浸出工艺条件为：硫酸用量为渣量的0.8倍,氢氟酸用量为渣量的0.6倍,反应温度为90℃,液固比为5∶1,反应时间为4 h,钽和铌的浸出率分别为99.80%和99.86%,终渣中钽和铌含量分别降至0.03%和0.01%。在最优条件下可得到含Ta2O59.50 g·L-1和Nb2O52.86 g·L-1的酸浸出液,可直接与现行工业生产中的钽铌萃取分离工艺衔接。全流程钽和铌回收率分别可达98.37%和99.15%。该工艺流程简单,操作条件温和,生产成本较低,具有显著的社会和经济效益。

英文摘要：

A new technique of comprehensive recovery of tantalum and niobium from tantalum-niobium residue by hydrometallurgical process composed of low-alkali decomposition-poaching, diluted acid preproeessing and transformation leaching was studied. The opti- mal technical conditions were measured by experiments. The conditions of low-alkali decomposition-poaching were as follows ： alkali-to- residue ratio of 0.6： 1.0, reaction temperature of 800 ℃, reaction time of 1 h, dosage of additive-NaC1 of 12% of the residue, temper- ature in water leaching of 90 ℃, ratio of fluid to solid of 6：1 and leaching time of about 0.5 h. The conversion rates of tantalum and niobium in alkali decomposition transformation were 92.3% and 98.2%, respectively. By dilute acid pretreatment, most of the impu- rities were removed, and the enrichment of tantalum and niobium was nearly 5 times that of the original residue. The conditions of transformation leaching were as follows ： dosages of sulfuric acid and hydrofluoric acid of 0.8 and 0.6 times the residue respectively, leaching temperature of 90 ℃, ratio of fluid to solid of 5：1 and leaching time of about 4 h. The leaching rates of tantalum and niobium in acid transformation leaching were 99.80% and 99.86% , respectively. The contents of tantalum and niobium in final residue dropped to 0. 03% and 0.01% , respectively. Under the optimal conditions, an acid solution containing 9.50 g·L-1 Ta205 and 2.86 g·L-1 Nb2 05 could be obtained, which could match with the tantalum-niobium extraction and stripping technology in the production of tantalum-niobium industry and the recovery rates of tantalum and niobium could reach 98.37% and 99.15%, respectively. The new process had many advantages, such as simple process, mild operating conditions, low production cost, and remarkable social and eco- nomic benefits