通过简单的还原方法在离子液体[BMMIM]PF6(1-丁基-2,3-二甲基咪唑六氟磷酸盐)中,以膦功能化离子液体[BMMIM][tppm](1-丁基-2,3-二甲基咪唑间三苯基膦单磺酸盐)为稳定剂制备了纳米钯催化剂.采用透射电镜(TEM)、X-射线衍射(XRD)、X-射线光电子能谱(XPS)等方法对纳米钯催化剂进行了表征.结果表明:[BMMIM][tppm]稳定的纳米钯催化剂分散均匀,平均粒径约为3.9 nm,且Pd(Ⅱ)完全转化为Pd(0).在喹啉加氢反应过程中,考察了稳定剂种类、稳定剂用量、溶剂、温度、压力等因素对喹啉选择性加氢的影响.在50oC和氢气压力为3.5MPa的温和条件下,纳米钯催化剂催化喹啉及其衍生物加氢显示出高活性和高化学选择性.在循环过程中,膦功能化离子液体稳定的纳米钯催化剂能保持良好的催化活性和化学选择性.%Through simple reduction method,the Pd nanocatalyst was prepared in[BMMIM]PF6by using phosphine functionalized i-onic liquid[BMMIM][tppm]as a stabilizing agent.The catalyst was characterized by transmission electron microscopy(TEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS).The results showed that Pd nanoparticles stabilized by[BMMIM] [tppm]were highly dispersed,the average size was about 3.87 nm and Pd(Ⅱ)was completely reduced to Pd(0).The influences of different stabilizers,the amount of the stabilizer,solvents,temperature and hydrogen pressure on selective hydrogenation of quinoline were investigated.Pd nanocatalyst exhibited high activity and chemoselectivity in hydrogenation of quinoline and its derivatives un-der mild conditions(50oC,3.5MPa H2).Pd nanocatalyst stabilized by phosphine functionalized ionic liquid could maintain satisfac-tory catalytic activity and chemoselectivity in catalytic recycles.
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