【作者】 薛芳；

【导师】 陈华；

【作者基本信息】 四川大学 ， 有机化学， 2006， 硕士

【摘要】 研究了负载型的高分散纳米贵金属催化剂和含钌的双金属催化剂催化吡啶及其衍生物的加氢性能。结果表明,含钌5%的Ru/C催化剂对吡啶氢化反应的活性最高,在钌催化剂中加入少量的第二种金属组分如Pd、Ir对催化活性没有明显的影响。用XRD、HRTEM和XPS对还原后的Ru/C催化剂表征,表明钌处于高分散零价态,其平均粒径小于5 nm。在100 oC, 3.0 MPa, Ru/吡啶= 2.5:1000(摩尔比)的条件下,反应1小时,吡啶加氢的转化率大于99.9%,生成哌啶的选择性为100%。催化剂重复使用5次,活性和选择性无明显下降。同时还对不同的吡啶衍生物的催化活性作了比较,其催化活性顺序为:吡啶≈2-甲基吡啶>2,6-二甲基吡啶>3-甲基吡啶>4-甲基吡啶>3,5-二甲基吡啶>2-甲氧基吡啶。将制备了高分散性负载型5%Ru/C催化剂,以及以活性炭负载的双金属催化剂和其它的单金属催化剂,用于喹啉选择性加氢反应的研究。考察了温度、压力、反应时间、溶剂等反应条件对喹啉加氢反应的转化率和选择性的影响。在100 oC、3 MPa、1 h、乙醇为溶剂及催化剂与底物的摩尔比为3:1000时,反应的主产物为部分加氢产物1,2,3,4-四氢喹啉,其转化率为98.7%,选择性为98.5%。并对喹啉的全加氢制得十氢喹啉进行了探索,在最佳反应条件下,延长反应时间或升高反应温度,都没有检测到十氢喹啉。只有在得到1,2,3,4-四氢喹啉后,添加新催化剂,继续反应才得到十氢喹啉。更多还原

【Abstract】 The highly dispersed supported noble metal catalysts were prepared and their catalytic perfermances in the hydrogenation of pyridine were investigated. Active carbon supported ruthenium catalyst was characterized by HRTEM、XRD and XPS . The active carbon supported ruthenium was reduced to zero valence and the average partical diameter of Ru crystallites was smaller than 5 nm. The results indicated that ruthenium catalyst exhibited the highest activity compared with palladium, platinium and iridium for the hydrogenation of pyridine. The order of catalystic activities is Ru/C > Pd/C > Pt/C > Ir/C. The activities of bimetallic catalysts Ru-Pd/C and Ru-Ir/C were slightly lower than that of Ru/C, but the activity of Ru-Co/C was much lower than that of Ru/C. It suggested that there was no synergetic effect between two metals. The comparing study on hydrogenation of pyridine derivatives showed that the electron factor played an important role in the reaction process. The reactivities of pyridine and its derivateves were pyridine as following : 2-methylpyridine > 2,6-dimethyl- pyridine >3-methylpyridine> 4-methylpyridine > 3,5-dimethylpyridine > 2-methoxy- pyridine. Under the optimum reaction conditions : 100 oC, PH2 = 3.0 MPa, Ru/pyridine = 2.5:1000 (molar ratio), pyridine could be completely converted to piperidine with the selectivity of 100%. The reuse of catalyst showed that the activity and selectivity of Ru/C did not decrease significantly.The catalytic behavior of 5% Ru/C was also investigated in the hydrogenation of quinoline and compared with other bimetallic catalysts (5%Ru-Pd/C, Ru-Ir/C)更多还原