离子液体作为绿色介质从盐湖卤水中萃取硼酸

Experiment on the Application of Ionic Liquid as Green Medium for Extraction of Boric Acid from Salt Lake Brine

制备了1-辛烷基-3-甲基咪唑六氟磷酸盐离子液体,再以离子液体(IL)为萃取介质、异辛醇为萃取剂及煤油为稀释剂建立盐湖卤水硼萃取研究模型,考察了离子液体用量和萃取条件对硼萃取的影响。异辛醇从卤水中萃取提硼的最佳实验条件:离子液体体积分数为10%,萃取剂体积分数为50%,相比(O/A)为1∶1,萃取时间10 min,pH 2.4,Mg2+浓度为4.268 mol/L。在此条件下,当萃取级数为3级时,萃取率为99.54%,卤水中的硼可被完全萃取到有机相中。

Ionic liquid is a green solvent for extraction of boron from salt lake beine as extraction medium. 1-octyl-3-methylimidazolium hexafluorophosphate ionic liquid was prepared and the ionic liquid, isooctyl alcohol and kerosene were used as extraction medium, synergic reagent and diluent respectively. The influence of ionic liquid dosage and extraction conditions on the boron extraction were investigated. The optimal experimental parameters were obtained as follows：ionic liquid dosage 10% ,the extractant 50% ,the ratio of organic phase to brine 1 ： 1, the extraction time 10 min, and pH 2.4. the concentration of Mg2~ 4. 268 mol/L. Under optimal conditions, the boron can be fully extracted to the organic phase with three step extractions and a recovey of 99.54% was obtained.