Trimodal Porous Hierarchical SSZ-13 Zeolite with Improved Catalytic Performance in the Methanol-to-Olefins Reaction

详细信息    查看全文

• 作者：Xiaochun Zhu ; Jan P. Hofmann ; Brahim Mezari ; Nikolay Kosinov ; Leilei Wu ; Qingyun Qian ; Bert M. Weckhuysen ; Shunsuke Asahina ; Javier Ruiz-Martínez ; Emiel J. M. Hensen
• 刊名：ACS Catalysis
• 出版年：2016
• 出版时间：April 1, 2016
• 年：2016
• 卷：6
• 期：4
• 页码：2163-2177
• 全文大小：926K
• ISSN：2155-5435

文摘

Chabazite zeolites with trimodal porosity (native micropores of the CHA framework, an additional network of larger micropores of ∼0.5 nm, and mesopores) were synthesized by adding diquarternary ammonium-type surfactant C_22–4–4 cations and fluoride anions in the synthesis of SSZ-13 zeolite. The hierarchical SSZ-13 zeolites are fully crystalline and exhibit similar acidity as bulk SSZ-13 zeolite. The increased diffusion rate in the hierarchical SSZ-13, proven by uptake experiments of bulky molecules and selective staining by thiophene oligomers, resulted in much slower catalyst deactivation in the methanol-to-olefins (MTO) reaction. Confocal fluorescent images of spent hierarchical SSZ-13 zeolites reveal homogeneous distribution of carbonaceous deposits, indicating that the micropore space has been completely utilized during the MTO reaction.