Center for Advanced Bioseparation Technology, Inha University, Incheon 402-751, South Korea.
J Chromatogr A. 2010 Dec 3;1217(49):7638-41. doi: 10.1016/j.chroma.2010.10.028. Epub 2010 Oct 11.
Microwave-assisted separation has been applied to recover ionic liquid (IL) from its aqueous solution as an efficient method with respect to time and energy compared to the conventional vacuum distillation. Hydrophilic ILs such as 1-butyl-3-methylimidazolium tetrafluoroborate ([Bmim][BF(4)]), 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([Bmim][TfO]) and 1-ethyl-3-methylimidazolium methylsulfate ([Emim][MS]) could be recovered in 6 min from the mixture of ILs and water (1:1, w/w) under microwave irradiation at constant power of 10 W while it took at least 240 min to obtain ILs containing same water content (less than 0.5 wt%) by conventional vacuum oven at 363.15 K with 90 kPa of vacuum pressure. Energy consumptions per gram of evaporated water from the homogeneous mixture of hydrophilic ILs and water (1:1, w/w) by microwave-assisted separation were at least 52 times more efficient than those in conventional vacuum oven. It demonstrated that microwave-assisted separation could be used for complete recovery of ILs in sense of time and energy as well as relevant purity.
微波辅助分离已被应用于从其水溶液中回收离子液体（IL），与传统的真空蒸馏相比，该方法在时间和能量方面具有高效性。亲水性 IL 如 1-丁基-3-甲基咪唑四氟硼酸盐 ([Bmim][BF(4)])、1-丁基-3-甲基咪唑三氟甲磺酸盐 ([Bmim][TfO]) 和 1-乙基-3-甲基咪唑硫酸甲酯盐 ([Emim][MS]) 可以在微波辐射下，在恒定功率为 10 W 的条件下，从 IL 和水（1:1，w/w）的混合物中在 6 分钟内回收，而通过传统的真空炉在 363.15 K 和 90 kPa 的真空压力下至少需要 240 分钟才能获得相同含水量（小于 0.5wt%）的 IL。从亲水性 IL 和水（1:1，w/w）的均相混合物中每蒸发 1 克水所需的能量消耗通过微波辅助分离比传统真空炉至少高 52 倍。这表明微波辅助分离在时间和能量方面以及相关纯度方面都可以用于 IL 的完全回收。
