负载离子液体的多孔催化材料的制备

合成一系列溴化咪唑类离子液体,用溶胶-凝胶法负载在硅胶上,制备出几种硅胶负载离子液体催化剂Cnmim]Br/silica gel。考察了负载过程中,离子液体种类、盐酸用量和Cnmim]Br与Teos物质的量的比对负载量的影响。把不同方法制得的Cnmim]Br/silica gel用丙酮在提取器中抽提,考察它们的负载牢度。IR光谱表征结果表明,离子液体已负载于硅胶上。适宜的合成条件:选用Emim]Br进行负载,盐酸用量15 mL,n(Teos)∶n(Emim]Br)为72∶1。用Emim]Br/silica gel催化酯化反应,酯化率为29.4%。重复使用4次仍然有催化活性。

Preparation of porous catalytical material supporting ionic liquids

Silica gel supporting ionic catalysts Br/silica gel was prepared after a series of N-Alkylimidazolium ionic liquids were synthesized and supported on the silica gel.The effect of ionic liquid species,amount of dydrochloric acid and n(Br)∶n(Teos) ratio on supporting quantity in the supporting process was studied.Br/silica gel prepared in different ways was extracted with acetone to test the supporting intension.The IR indicated that the ionic liquids were fixed on silica gel.The optimization for catalyst preparation as follow: Br was chosen to be supported,hydrochloric acid mount was 15 mL,n(Teos)∶n(Br) was 72∶1.When Br/silica gel was used as catalyst in esterification reaction,the rate of esterification was 29.4%.It was found that the catalyst still had catalytic activity after used 4 times.