ZSM-35分子筛二次孔分布改性及其催化性能研究

Modification of Secondary Pore Distribution of ZSM-35 Molecular Sieve and Catalytic Performance

采用在ZSM-35分子筛成型阶段添加扩孔剂,通过高温焙烧的方式去除模板剂的同时使添加的扩孔剂不断气化从而产生特定大小的孔隙。所制备的ZSM-35分子筛在没有降低强度的同时产生了大量的均匀分布的二次孔,二次孔大多集中在5 nm左右,这些大小均一且分布集中的二次孔,有效的解决了反应物和产物的扩散问题,从而提高了催化剂的选择性。最后将其应用于正丁烯骨架异构化制备异丁烯小试评价中,其中异丁烯的选择性可达91%,表现出了优异的催化性能。

The pore expander was added in the ZSM-35 molecular sieve forming stage. The template was removed by high temperature roasting, and the pore expander was gasified continuously to produce specific size pores. The ZSM-35 zeolites produced a large number of uniformly distributed secondary pores without reducing the strength. Most of the secondary pores were concentrated at about 5 nm, which effectively solved the diffusion problem of reactants and products and improved the selectivity of the catalyst. Finally, it was applied to the pilot scale evaluation of n-butene skeleton isomerization to isobutene. The selectivity of isobutene was up to 92 %.