N263从钼酸钠溶液中萃取分离钼钒

采用季铵盐萃取剂N263, 从高浓度钼酸钠溶液中选择性萃取V, 考察有机相组成、平衡pH值、接触时间、温度、相比对钼钒萃取的影响, 探索萃取后负载有机相选择性洗涤除Mo的条件.结果表明, 在有机相组成为15 % N263、12 %仲辛醇、料液pH值为8.50、相比V_O/V_A=1: 2、混合时间5 min、温度25 ℃的条件下, 经过5级逆流萃取, V的萃取率大于99.60 %, Mo的萃取率低于0.5%, 钒钼的分离系数β_V/Mo可达63 000;采用0.1 mol/L NaCl+0.3 mol/L NaHCO₃为洗涤剂, 在相比V_O/V_A=5: 1, 混合时间5 min、温度25 ℃的条件下, 经过5级逆流洗涤, 负载有机相中Mo的洗脱率达到98.87 %, 且V的损失率在0.4 %以下; 经反萃可得到含V 51.33 g/L, Mo < 0.03 g/L的钒酸钠溶液, 实现了钼钒的分离. 

Separation of vanadium from sodium molybdate solution by N263

A quaternary ammonium salt was used to selectively extract vanadium from high concentration sodium molybdate solution. The effects of extractant composition, equalized pH value, contract time, reaction temperature, phase ratio on molybdenum and vanadium extraction were investigated. Selectively removed molybdenum from loaded organic phase was also studied. The results show that the extraction rate of vanadium can reach 99.60 % through five-stage countercurrent extraction with extractant composition of 15 % quaternary ammonium salt +12 % DL-2-octanol+73 % sulfonated kerosene, pH rate of 8.50, V_O/V_A ratio of 1: 2 at 25 ℃ for 5 minutes, while the molybdenum extraction rate is under 0.5 %, the separation coefficient of βV/Mo up to 63 000. The loaded organic is washed by 0.1 mol/L NaCl+0.3 mol/L NaHCO₃, on the condition of V_O/V_A ratio of 5: 1, contract time of 5 min, temperature of 25 ℃. Through five-stage countercurrent washing, 98.87 % of molybdenum and 0.4 % of vanadium are removed. Through stripping can achieve sodium vanadate solution, which contain 51.33 g/L of vanadium and molybdenum concentration is under 0.03 g/L. The study achieves separation of molybdenum and vanadium.