影响离子液体迁移的盐析和离子对效应  

Effect of Salting-Out and Ion-Pairing on Column Transport of Ionic Liquids

作　　者：魏丽 祝凌 邱宇平[1] 

机构地区：[1]同济大学环境科学与工程学院,上海

出　　处：《水污染及处理》2019年第2期91-100,共10页Water Pollution and Treatment

摘　　要：本文研究了五种阴离子不同的1-丁基-3-甲基咪唑基(Bmim+)离子液体在活性炭柱上的迁移行为,发现阴离子可通过与Bmim+的结合来改变离子液体的辛醇–水分配系数(Kow)和离子对结合常数(KIP),从而影响离子液体的柱迁移能力。一般来说,Kow和KIP越大,离子液体吸附能力越强,迁移能力越弱。外加磷酸根(PO43-)阴离子,可使离子液体的迁移能力下降约60%,这得益于盐析效应的促进作用;而外加双三氟甲磺酰亚胺(NTf-2)阴离子,能促进强疏水[Bmim][NTf2]离子对的生成,使得离子液体的迁移能力下降约81%。In this work,the transport of five kinds of 1-n-Butyl-3-methylimidazolium(Bmim+)based ILs cou-pled with different counter anions in activated carbon column is studied.It is found that the counter anions can change the octanol-water partition coefficient(Kow)and the ion-pair formation constant(KIP)of ILs by binding with Bmim+cation,thus affecting the column transport ability of ionic liquids.In general,the greater the Kow and KIP,the stronger the ILs adsorption and the weaker the ILs transport.The addition of PO43-anions decreases the transport of ILs by about 60%,which is due to the effect of salting out.Moreover,the addition of NTf-2 anions can promote the formation of stronger hydrophobic[Bmim][NTf2]ion pair,thereby decreasing ILs transport by approximately 81%.

关 键 词：离子液体 柱迁移 盐析效应 离子对效应 

分 类 号：O64[理学—物理化学]