Engineering three-layer core–shell S-1/TS-1@dendritic-SiO_(2) supported Au catalysts towards improved performance for propene epoxidation with H_(2) and O_(2)

• 作者: Zhaoning Song Juncong Yuan Zhenping Cai Dong Lin Xiang Feng Nan Sheng Yibin Liu Xiaobo Chen Xin Jin De Chen Chaohe Yang
• 来源期刊: 绿色能源与环境:英文版
• 学科: 化学
• 关键词: Propene epoxidation Selectivity Core-shell Dendritic SiO_(2)shell TS-1
• 年，卷（期）: 2020,（4）
• 页码范围: 473-483
• 页数: 11页
• 分类号: O62

摘要

The advocacy of green chemical industry has led to the development of highly efficient catalysts for direct gas-phase propene epoxidation with green,sustainable and simple essence.The S-1/TS-1@dendritic-SiO_(2) material with three-layer core–shell structure was developed and used as the support for Au catalysts,which showed simultaneously fantastic PO formation rate,PO selectivity and stability(over 100 h)for propene epoxidation with H_(2) and O_(2).It is found that silicalite-1(S-1)core and the middle thin layer of TS-1 offer great mass transfer ability,which could be responsible for the excellent stability.The designed dendritic SiO_(2) shell covers part of the acid sites on the external surface of TS-1,inhibiting the side reactions and improving the PO selectivity.Furthermore,three kinds of SiO_(2) shell morphologies(i.e.,dendritic,net,mesoporous shell)were designed,and relationship between shell morphology and catalytic performance was elucidated.The results in this paper harbour tremendous guiding significance for the design of highly efficient epoxidation catalysts.