三苯基膦稳定的负载钌纳米粒子上对氯硝基苯的选择加氢反应

摘要

制备了γ-Al2O3负载的三苯基膦稳定的钌纳米粒子(PPh3-Ru/Al2O3)催化剂,并进行了XRD和XPS表征.将其用于对氯硝基苯的选择加氢反应,考察了反应压力、温度和时间对催化性能的影响.结果表明,在60℃、氢压2 MPa、反应21 h和对氯硝基苯几乎完全转化的条件下,实现了产品对氯苯胺99.7%的选择性.分析表明,脱氯反应的抑制是取得产品高选择性的主要原因,阐明了该催化剂如何有效抑制脱氯反应的发生.%γ-Al2O3 supported triphenylphosphine-stabilized ruthenium nanoparticle catalyst was prepared and characterized by XRD and XPS. The effect of hydrogen pressure, temperature and reaction time on the hydrogenation of p-chloronitrobenzene over PPh3-Ru/γ-Al2O3 catalyst was investigated. Under the reaction condition of 60℃, hydrogen pressure 2.0 MPa, reaction for 21 h, and p-chloronitrobenzene conversion of 100%, selectivity to p-chloroaniline of 99.7% was obtained. The suppression of dehaloge-nation reaction was responsible for high selectivity to p-chloroaniline. The reason for the suppression of dehalogenation reaction over PPh3-Ru/Al2O3 catalyst was also clarified.