超声波辅助法合成离子液体[C2OHmim]BF4及其双水相体系的研究

Ultrasonic–Assisted Synthesis of N-(2- Hydroxyl ethyl)-3- methyl imidazole terafluoroborate ionic liquid and Applied for Aqueous Two-phase System

摘要:

采用超声波辅助法的方法合成 N-(2-羟乙基）-3-甲基咪唑四氟硼酸盐 ([C2OHmim]BF4)，产率为57.69%。与传统合成方法相比，缩短了反应时间，提高了产率。建立了[C2OHmim]BF4和无机盐形成的离子液体双水相体系。实验结果表明，盐的种类和浓度对体系的形成影响很大，(NH4)2SO4能与[C2OHmim]BF4水溶液形成双水相体系。2mL的[C2OHmim]BF4和3mL水溶液中加入0.7000g (NH4)2SO4时，形成稳定双水相且相比达为2.4∶2.6，接近于1；在pH=6～9时，溶液酸度对体系的相比影响较小；在不同温度下体系的热稳定性较好，受温度影响不大；离子液体可再利用。

Abstract:

The N-(2- Hydroxyl ethyl)-3- methyl imidazole terafluoroborate ([C2OHmim]BF4) were synthesized under the conditions of ultrasound intermittent operation．The yield was 57.69％. Compared with conventional synthesis, the reaction time was drastically reduced and the higher yield was obtained． Then [C2OHmim]BF4 was used for aqueous two-phase system (ATPS). The result shows that salt kind and its concentration had important influence on ATPS. The thermal stable ATPS can be formed as follows: 2mL [C2OHmim]BF4 , 3mL water , 0.7500g (NH4)2SO4 and 25 degree. The phase volume ratio of system was 2.4∶2.6 about PH 6～9. [C2OHmim]BF4can be reused for extraction.