Low-Acid Extraction of Tantalum from a Tantalum-Niobium Pulp by MIBK

The technological parameters and the mechanism of low-acid pulp extraction of tantalum were investigated.The results show that hydrofluoric acid concentration, sulfuric acid concentration, organic to pulp phase ratio, the concentration of tantalum and niobium, contact time and temperature have a significant effect; optimum process operating parameters were established as follows: hydrofluoric acid concentration 1.6 mol/L, sulfuric acid concentration 0.6 mol/L, organic to pulp phase ratio 3:1, tantalum concentration 26.61 g/L, niobium concentration 11.64 g/L, contact time 5min and room temperature.Under these experimental conditions, tantalum extraction can reach more than 98% and the separation factors of Ta/Nb, Ta/Fe and Ta/Sn were maximal.According to slope analysis, the equimolar series method and the saturation capacity method, the extraction product was identified as 3MIBK•H 2 TaF 7 .