提高钛白废酸提钪萃取选择性的研究

研究旨在选择合适的助萃剂LH，提高二（2-乙基己基）磷酸（P204）-磷酸三丁酯（TBP）-磺化煤油体系对钛白废酸提钪的选择性，提高钪钛分离系数和钪铁分离系数。研究采用的工艺为二次萃取富集、二次反萃成钪、化学精制提纯钪。通过正交试验确定最佳萃取工艺条件：萃取剂最佳配比V（P204）∶V（TBP）∶V（磺化煤油）=1.3∶0.7∶10，一次萃取相比为V（O）∶V（A）=1∶21，不加助萃剂二次萃取相比为V（O）∶V（A）=1∶5，加助萃剂时其加量为水相体积的1.7%，此时钪钛分离系数达到124 812，钪铁分离系数达到8 202。

Study on improving selectivity of scandium extraction from titanium white waste acid

The study aimed to select the appropriate synergic reagent LH，to increase the selectivity of scandium extraction from titanium white waste acid with the di-（2-ethylhexyl） phosphoric acid（P2O4）-tributyl phosphate（TBP）-sulfonated kerosene system，and to improve scandium-titanium separation coefficient and scandium-iron separation coefficient.The process including secondary extraction enrichment，secondary stripping for scandium，and chemical purification was adopted. Through orthogonal test，the optimum extraction conditions were obtained as follows：the best extractant volume ratio of P2O4∶TBP∶sulfonated kerosene=1.3∶0.7∶10， the first extraction phase ratio［V（O）∶V（A）］ was 1∶21， without synergic reagent LH， the secondary extraction phase ratio［V（O）∶V（A）］ was 1∶5，and the dosage of synergic reagent LH was 1.7% of the volume of the aqueous phase. Under those conditions the scandium-titanium separation coefficient reached 124 812，and scandium-iron separation coefficient reached 8 202.