TBP−仲辛醇协同萃取钽铌萃余液中低浓度钽、铌和钨

Synergistic solvent extraction of Ta/Nb/W from Ta/Nb extraction raffinate by using TBP and 2-octanol as extractants

采用TBP−仲辛醇混合萃取剂对钽铌矿萃余液中低浓度钽、铌和钨等有价资源进行综合回收。研究TBP与仲辛醇的体积比、稀释剂含量、溶液酸度、萃取相比、萃取温度以及萃取时间等因素对钽、铌和钨回收率及分相时间的影响规律。结果表明:TBP−仲辛醇混合萃取剂对钽铌矿萃余液中低浓度钽、铌和钨具有较好的协同萃取效果。单因素实验结果表明,TBP与仲辛醇体积比控制在1:1时比较合适。在此条件下,进一步通过正交实验确定最优实验方案:稀释剂20%,H+浓度16 mol/L,相比2:1,温度25℃,萃取反应时间4 min。在最优条件下,钽铌的总回收率为98.53%,钨的回收率为89.62%,综合回收效果较为理想。

The solvent extraction of Ta/Nb/W from Ta/Nb extraction raffinate was studied on a synergistic solvent extraction system by using TBP and 2-octanol as the extractants.The effects of volume ratio of TBP and 2-octanol,diluent content,solution acidity,extraction ratio,extraction temperature and extraction time on Ta,Nb and W recovery rates and phase separation time were investigated.The results show that the synergistic effect observed in the TBP and 2-octanol system has improved the extraction efficiency.Through single-factor,the volume ratio of TBP and 2-octanol of 1:1 is more appropriate.Under this condition,the optimal experimental is further confirmed by the orthogonal experiment with 20%of diluent,16 mol/L of acidity,2/1 of extraction ratio,25℃of extraction temperature and 4 min of extraction time.Under the optimal conditions,the total recovery rate of Ta+Nb is 98.53%,and the recovery rate of W is 89.62%.The comprehensive recovery is very good.