(107a) Designed Synthesis of STA-30: A Small Pore Zeolite Catalyst with Topology Type Swy

The synthesis of small pore zeolites continues to offer new framework topologies for a range of catalytic reactions and adsorptive separations. Frameworks built from the stacking of 6Rs in the ABC-6 family have been a fruitful source of important materials, including SSZ-13. As well as aluminosilicate zeolites, the family includes several AlPO₄-based zeotypes, some of which have no zeolite analogues, which constitute a promising source of target frameworks for synthesis. Seven such topologies have been prepared initially as SAPOs, but only two of these have subsequently been synthesised as aluminosilicates (AFX and AFT). Here we present an addition to this group in the form of STA-30, an aluminosilicate material with the SWY topology, which had been observed previously only as the SAPO, STA-20 (Turrina et al., 2017). It has been prepared by a designed synthesis that took into account both inorganic and organic cations as structure directing agents, and involved molecular modelling of the family of 1,n-(1,4-diazabicyclo[2.2.2]octane)alkyl (diDABCO-Cn) molecules to inform our choice of templates for the swy cage. Synthetic results, including product crystallinity, can be related to the computational study. Additional experimental variables have been optimised to enable scale-up and to allow variation in Si/Al ratio of the product. The as-prepared STA-30 is stable to calcination, ion exchange and activation, giving a three-dimensional small pore structure. As well as being an acid catalyst, as shown by ¹H MAS-NMR for the proton form, STA-30 is active for selective catalytic reduction of NO with NH₃ under realistic conditions when prepared in the Cu-exchanged form. Solid state NMR was also used to monitor the Al species present in this material at the various stages of post-synthetic modifications and to obtain a Si/Al ratio from its ²⁹Si spectrum, which has been challenging in the past for other similar materials.