Constrained Al sites in FER-type zeolites

Crystallographic sites of Brönsted acids (Si-OH-Al) in zeolites, which are closely associated with the Al sites, play a significant and unique role catalytic application, especially when they distributed open channel systems or confined cavities small pore openings. In this article, we unraveled constrained crystallographic FER-type zeolites containing distinct local environments (10-ring channels ferrierite cavities) by Rietveld refinement against powder X-ray diffraction data. Final demonstrates that regardless types structure-directing agents synthetic medium utilized, T1 and/or T3 Al-rich positions, further confirmed theoretical calculations. This new finding zeolite can well explain its limited activity DME carbonylation reaction.