An attempt has been made to develop a fast, efficient and eco-friendly process for extraction of drug; Rifampicin (RF) from its aqueous solutions using room temperature ionic liquids (RTILs). RTILs viz. 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-butyl-3-methylimidazolium tetrafluoroborate and 2-Hydroxyethyl-trimethylammonium L-(+)-lactate have been used for removal of RF. Various factors such as hydrophilicity/hydrophobicity of RTILs, concentration of used RTILs and pH of drug solutions, affecting removal of RF from its aqueous solution have been studied to investigate mechanism of extraction process. Partition coefficient of RF between RTILs and aqueous phases as well as its extraction efficiency have also been calculated and analyzed. Results showed that hydrophobicity plays a major role in extraction of RF from its aqueous solutions. The addition of just 2 % of hydrophobic RTIL; [BMIM][PF6] leads to almost complete precipitation (98.92 %) of RF in just 1 min. Also, it has been observed that extraction efficiency of [BMIM][PF6] is maximum at pH = 8.

中文翻译：

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室温离子液体从水中提取和回收利福平及其机理研究

已经尝试开发一种快速，有效和环保的药物提取工艺；使用室温离子液体（RTIL）从其水溶液中分离利福平（RF）。RTIL，即 六氟磷酸1-丁基-3-甲基咪唑鎓，双（三氟甲基磺酰基）酰亚胺1-乙基-3-甲基咪唑鎓，四氟硼酸1-丁基-3-甲基咪唑鎓和L-（+）-乳酸2-羟乙基三甲基铵已被用于去除RF。 。研究了多种因素，如RTIL的亲水性/疏水性，使用过的RTIL的浓度和药物溶液的pH值，影响了RF从其水溶液中的去除，以研究提取过程的机理。RTILs和水相之间的RF分配系数及其提取效率也已计算和分析。结果表明，疏水性在从水溶液中提取射频中起主要作用。仅添加2％的疏水性RTIL；[BMIM] [PF6]仅在1分钟内导致RF几乎完全沉淀（98.92％）。另外，已经观察到[BMIM] [PF6]的萃取效率在pH = 8时最大。