Research on Recovery of Tantalum and Niobium from Tungsten Residue by Acid Method

This paper describes a new technology which is used to recover tantalum and niobium from tungsten residues with the method of acid treatment,which includes diluted acid treatment for desilication,concentrated acid treatment for iron and manganese removal,HF acid leaching of tantalum and niobium and evaporation concentration.Using this method,the tungsten residues containing 0.14% tantalum and 0.59% niobium can be processed.The optimal technical conditions are ensured by experiments.Under the optimal condition,HF acid solution containing 8.0 g/L Ta2O5 and 35.4 g/L Nb2O5 can be obtained which can be used in the production of tantalum-niobium industry and the recovery rate of tantalum and niobium can reach above 80%.With this method,the recovery of tantalum,niobium and silicon in the tungsten residues can be realized and the environmental pollution caused by large amounts of tungsten residues can be decreased.