为了从高镁锂比卤水中提锂，需要解决锂镁分离，本文用二苯并-14-冠-4(DB14C4)来达到此目的。用超声波合成法，在常温、短时反应条件下以42．22%的产率得到DB14C4。对DB14C4采用高斯频率计算与其实测红外光谱比对来确定产物结构。考察了DB14C4及其与有机磷酸酯协同配位萃取对锂镁分离的效果，实验结果表明：单一的DB14C4对锂离子的萃取率仅为2%，对锂镁混合液中锂离子的选择性系数为1．20。当DB14C4与有机磷酸酯构成的协同体系【即DB14C4与二(2-乙基己基)磷酸酯(B2EHPA)】，则对锂离子的萃取率增大到36%，选择性系数增加到6．17。动态液膜迁移实验也证实了协同配位体系能增加其对锂离子的选择性，当DB14C4与B2EHPA摩尔比为2∶1时，动态迁移选择率达到9．7。%To extract lithium from salt lake brine with high magnesium lithium ratio,the separation of lithium and magnesium need to be solved,and dibenzo-14-crown-4(DB14C4)was used for the purpose. With ultrasonic synthetic method,under the condition of normal temperature and short reaction time,DB14C4 was synthesized with the yield of 42. 22%. The structure of DB14C4 was ob-tained by comparing its infrared spectrum and the gaussian frequency. The effects of lithium magnesium separation was examined by the DB14C4 and its coordination with organic phosphate. The result of experiment showed that lithium ion extraction rate was only 2%using the single DB14C4,the selective coefficient of lithium ion extracting from mixture of lithium and magnesium was only 1. 2. When the synergistic coordination system composed of DB14C4 and bis-(2-ethylhexyl)phosphate(B2EHPA),the extraction rate of lithium ion increased to 36%,the selectivity coefficient increased to 6. 17. Dynamic migration of liquid membrane extraction experiments had confirmed that the synergistic extraction system could increase the lithium ion selective,when the rnolar ratio of DB14C4 to B2EHPA was 2 ∶ 1,the selective migration coefficient was the highest of all,it was 9. 7.
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