离子液体[bmim]PF_6中制备纳米金属Ni及其催化苯乙烯加氢的研究  

Preparation of nano Ni catalyst in ionic liquids [bmim] PF_6 and its application in the styrene hydrogenation

作　　者：王雪涛[1] 余林[1] 彭兰乔[1] 孙明[1] 许洁瑜[1] 余倩[1] 余坚[1] 

机构地区：[1]广东工业大学轻工化工学院,广东广州510006

出　　处：《功能材料》2008年第3期519-522,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(20203012);广东省科技计划资助项目(2005B10201053);广东省自然科学基金团队资助项目(4205301);广东省高等学校自然科学研究重点资助项目(06Z011);广州市科技计划资助项目(2006J1-C0501)

摘　　要：以化学还原手段分别在水溶液和离子液体1-丁基-3-甲基咪唑六氟磷酸盐([bmim]PF6)中制备了纳米金属Ni粉末,采用X射线衍射(XRD)、透射电镜(TEM)、傅立叶红外光谱(FT-IR)、紫外可见光谱(UV-vis)及热重(TG-DTA)对所制备样品的形貌和结构进行了表征。XRD表征结果显示:与水溶液制备纳米Ni相比,在[bmim]PF6中制备的纳米Ni具有立方相结构,无氧化峰出现;TEM结果显示:在[bmim]PF6中制备的纳米Ni具有更小的粒径和更好的颗粒分布,团聚现象不明显;FT-IR显示:离子液体不仅仅作为反应的介质,而且和纳米颗粒表面间存在着一定的化学结合,吸附在纳米颗粒的表面,有效的阻止了Ni纳米颗粒的团聚和氧化;TG-DTA及UV-vis结果进一步验证了Ni表明离子液体层的存在。苯乙烯加氢产物的分析结果表明,在[bmim]PF6中制备的纳米Ni催化苯乙烯加氢的活性显著高于常规制备的Ni催化剂。Nano Ni particles were prepared by chemical reduction method in aqueous solution and 1-butyl-3-methylimidazolium hexafluorophosphate （[bmim]PF6）, respectively. The prepared catalysts were characterized by TG-DTA and UV-vis with a layer of ionic liquid absorbed in the surface of Ni catalyst, by FT-IR with a strong coordination between Ni catalyst and ionic liquid, by XRD as cubic structure and no peak of oxidation, by TEM with a particle size distribution in the range of 10-12nm and good dispersion. The new Ni catalyst was found to significantly increase the catalytic activity for styrene hydrogenation compared with that prepared in conventional way. An excellent catalytic activity, with a styrene conversion of 57. 09% and phenylethylene yield of 66.81% in the reaction of styrene hydrogenation, could be obtained over the new Ni catalyst. This indicated that ionic liquid [bmim]PF6 might play a key role to stabilize nano catalyst and prevent aggregation of active nano particles.

关 键 词：离子液体 镍 化学还原 催化剂 苯乙烯加氢 

分 类 号：O643[理学—物理化学]