Pt-Ru/Nb_(2)O_(5)-SiO_(2)催化甘油氢解中Ru的促进机制研究  

Promoting mechanism of Ru in glycerol hydrogenolysis catalyzed by Pt-Ru/Nb_(2)O_(5)-SiO_(2)

作　　者：张元凯 周政 郑晓明 曹约强 周静红[1] ZHANG Yuankai;ZHOU Zheng;ZHENG Xiaoming;CAO Yueqiang;ZHOU Jinghong(State Key Laboratory of Chemical Engineering,School of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学化工学院化学工程联合国家重点实验室,上海200237

出　　处：《石油化工》2023年第11期1497-1504,共8页Petrochemical Technology

基　　金：国家自然科学基金项目(22178102)。

摘　　要：采用顺序浸渍法引入第二金属Ru,制备了Pt-Ru/Nb_(2)O_(5)-SiO_(2)催化剂用于强化甘油氢解反应,并利用XRD、N2吸附-脱附、H2-TPR、H2-TPD、NH3-TPD、XPS、HAADF-STEM等方法考察了Ru的促进机制。实验结果表明,Ru的引入量与催化活性呈“火山型”曲线关系,当Ru负载量为4%(w)时,Pt-Ru/Nb_(2)O_(5)-SiO_(2)活性最高,产物分布几乎不受影响。Ru物种与Pt物种产生了协同作用,显著增强了Pt的还原程度,改善了Pt的电子结构,有利于氢的解离和活性氢物种的生成;同时Ru对Pt的修饰也增加了催化剂表面的弱酸性位含量,为甘油吸附提供了更多的吸附位点,显著提升了Pt-Ru/Nb_(2)O_(5)-SiO_(2)催化甘油氢解的活性。The metal Ru was introduced into catalysts by sequential impregnation method to prepare bimetallic Pt-Ru/Nb_(2)O_(5)-SiO_(2)catalysts,enhancing their activity for glycerol hydrogenolysis.The promoting mechanism of Ru were studied by XRD,N2 adsorption-desorption,H2-TPR,H2-TPD,NH3-TPD,XPS and HAADF-STEM.The experimental results show a“volcano-shaped”curve relationship between the amount of introduced Ru and the catalytic activity.Pt-4Ru/Nb_(2)O_(5)-SiO_(2)catalyst with a Ru loading amount of 4%(w)displays the highest activity,while the product distribution remains largely unaffected.A synergistic effect between the Ru and Pt species significantly enhances the reducibility of Pt improves the electronic structure of Pt,and facilitates the dissociation of H2 and the generation of active H species.Simultaneously,the modification of Pt by Ru also increases the content of weak acid sites on the catalyst surface,providing more adsorption sites for glycerol adsorption,significantly enhancing the catalytic activity of Pt-Ru/Nb_(2)O_(5)-SiO_(2)for glycerol hydrogenolysis.

关 键 词：PT催化剂 RU 促进作用 甘油氢解 

分 类 号：TQ203.2[化学工程—有机化工]