摘要
为了改进催化剂孔结构的稳定性以及催化剂的机械强度,采用将三种原料并流滴加的方式制备了含硅拟薄水铝石前驱体,通过喷雾干燥成型获得了不同硅含量的微球形SiO_(2)-Al_(2)O_(3)载体,然后采用浸渍法制备了Pd/SiO_(2)-Al_(2)O_(3)催化剂,并应用于流化床蒽醌加氢过程。研究发现:三股并流滴加法可使硅原子均匀分散在初生粒子及后续晶化形成的层状结构拟薄水铝石中,有效解决了硅在载体中富集及对孔道的堵塞问题;硅的引入显著提高了微球形SiO_(2)-Al_(2)O_(3)的耐磨损性和水热稳定性。Pd/SiO_(2)-Al_(2)O_(3)催化剂的结构表征及蒽醌加氢性能评价结果表明:当Pd/SiO_(2)-Al_(2)O_(3)催化剂中SiO_(2)含量为8%质量分数时,催化剂的平均氢化效率为15.1 g/L,H_(2)O_(2)生产效率达到6040 kg/(kg-Pd·d),选择性保持在98.5%以上。
In order to improve the low mechanical strength and poor structure stability of catalysts,a three-strand parallel flow method was proposed to prepare silica-containing pseudo-boehmite precursor.The microsphere SiO_(2)-Al_(2)O_(3)carrier with different silicon contents was obtained by spray drying with the precursor.Then Pd/SiO_(2)-Al_(2)O_(3)catalyst was further prepared by impregnation method and applied in the hydrogenation process of anthraquinone in the fluidized bed.It was found that the three-strand parallel flow drop addition method could make the silicon atoms evenly dispersed in the primary particles and the layered structure pseudo-boehmite formed by subsequent crystallization,which effectively solved problems of the silicon enrichment in the carrier and the blockage of the pore channels.With the introduction of silicon,the wear resistance and hydrothermal stability of the microsphere SiO_(2)-Al_(2)O_(3)were significantly improved.The structure characterization of Pd/SiO_(2)-Al_(2)O_(3)catalyst and the evaluation of anthraquinone hydrogenation performance showed that the average hydrogenation efficiency of the catalyst was 15.1 g/L and the production efficiency of H_(2)O_(2)was up to 6040 kg/(kg-Pd·d)when the mass fraction of SiO_(2)in Pd/SiO_(2)-Al_(2)O_(3)catalyst was 8%,and the selectivity was kept above 98.5%.
作者
闫冲
陈帅
李家乐
刘雅楠
贺宇飞
李殿卿
YAN Chong;CHEN Shuai;LI Jiale;LIU Yanan;HE Yufei;LI Dianqing(Beijing University of Chemical Technology,Beijing 100029,China)
出处
《化学反应工程与工艺》
CAS
2021年第3期235-243,共9页
Chemical Reaction Engineering and Technology
基金
国家重点研发计划(2016YFB0301600)。
