Ru@Al_(x)-mSiO_(2)中空介孔核壳型催化剂苯酚加氢脱氧制苯性能研究  

Study on performances of Ru@Al_(x)-mSiO_(2)hollow mesoporous core-shell catalysts for phenol hydrodeoxygenation to benzene

作　　者：钟梦宇 于洪波 周永柱 尹宏峰[2] ZHONG Mengyu;YU Hongbo;ZHOU Yongzhu;YIN Hongfeng(School of Science,Tianjin Chengjian University,Tianjin 300384,China;Ningbo Institute of Materials Technology and Engineering,Chinese Academy of Sciences,Ningbo 315201,Zhejiang,China;School of Materials and Chemical Engineering,Ningbo University of Technology,Ningbo 315211,Zhejiang,China)

机构地区：[1]天津城建大学理学院,天津300384 [2]中国科学院宁波材料技术与工程研究所,浙江宁波315201 [3]宁波工程学院材料与化学工程学院,浙江宁波315211

出　　处：《低碳化学与化工》2024年第11期43-49,69,共8页Low-Carbon Chemistry and Chemical Engineering

基　　金：国家自然科学基金(22072171);天津市教委科研计划项目(2017KJ064)。

摘　　要：为解决负载型Ru催化剂在酚类化合物加氢脱氧反应中稳定性差的问题,以含Ru的二氧化硅微球(Ru@SiO_(2))为前驱体、偏铝酸钠(NaAlO_(2))为铝源,在碱性条件下通过选择性蚀刻制备了一系列不同Al负载量(质量分数)的中空介孔核壳型催化剂Ru@Al_(x)-mSiO_(2)(x=0.5、1.0、1.5或2.0)。采用TEM、HAADF-STEM、XRD、N_(2)吸/脱附、NH_(3)-TPD和H_(2)-TPD等对催化剂的微观结构和理化性质进行了表征。以苯酚加氢脱氧制备苯为模型反应,考察了Ru@Al_(x)-mSiO_(2)催化剂的催化性能。结果表明,在60℃、2.0 MPa的反应条件下,向Ru@mSiO_(2)中引入Al能显著提高苯选择性,这是因为Al的负载提供了丰富的酸性位点,其不仅可以辅助金属Ru解离H_(2)增加苯酚加氢活性,还能够增强苯酚的脱氧性能进而提高苯选择性。在所有催化剂中,Ru@Al1.0-mSiO_(2)展现出了最高的苯酚转化率(80.5%)和苯选择性(96.5%),这归因于金属Ru与硅铝酸盐壳层间的协同效应。此外,由于中空介孔硅铝酸盐壳层的限域保护作用,Ru@Al1.0-mSiO_(2)催化剂在多次催化循环加氢脱氧实验后,仍展现出了优异的稳定性。In order to address the issue of poor stability of loaded Ru catalysts in the hydrodeoxygenation reaction of phenolic compounds,a series of hollow mesoporous core-shell catalysts,Ru@Al_(x)-mSiO_(2)(x=0.5,1.0,1.5 or 2.0),with varying Al loadings(mass fractions)were prepared by selective etching under alkaline conditions with Ru-containing silica microspheres(Ru@SiO_(2))as the precursor and sodium meta-aluminate(NaAlO_(2))as the aluminum source.The microstructures and physicochemical properties of the catalysts were characterized by TEM,HAADF-STEM,XRD,N_(2) adsorption/desorption,NH3-TPD and H_(2)-TPD.The catalytic performances of Ru@Al_(x)-mSiO_(2)catalysts were investigated using phenol hydrodeoxygenation to prepare benzene as a model reaction.The results show that the incorporation of Al into Ru@mSiO_(2)under the reaction conditions of 60℃and 2.0 MPa can significantly improve the selectivity of benzene.This is attributed to the fact that the Al loading provideds abundant acidic sites,which can not only assist the dissociation of H_(2) from the metal Ru to increase the phenol hydrogenation activity,but also enhance the deoxygenation of phenol and thus improve the benzene selectivity.Among all the catalysts,Ru@Al1.0-mSiO_(2)exhibits the highest phenol conversion(80.5%)and benzene selectivity(96.5%),which is attributed to the synergistic effect between the Ru metal and the silicoaluminate shell layer.Furthermore,the hollow mesoporous silica-aluminate shell layer exhibites a domain-limiting protective effect,and Ru@Al1.0-mSiO_(2)still exhibits excellent stability in multiple catalytic cycle hydrodeoxygenation experiments.

关 键 词：酚类化合物 Ru基核壳型催化剂 苯酚 加氢脱氧 苯 

分 类 号：TQ426[化学工程]