The first zeolite with a tri-directional extra-large 14-ring pore system derived using a phosphonium-based organic molecule
(English)Manuscript (preprint) (Other academic)
A new germanosilicate zeolite (denoted as ITQ-53) with extra-large 14-ring pores has been synthesized using tri-tertbutylmethylphosphonium cation as the organic structure directing agent (OSDA). The new rotation electron diffraction (RED) method was used to both identify and solve the structure of ITQ-53 from an initially synthesized sample containing impurities, which facilitated the synthesis optimization that led to pure ITQ-53. The structure was refined against PXRD data. ITQ-53 is the first example of extra-large pore zeolites with tri-directional interconnected 14 × 14 × 14-ring channels. It is built from double 3-rings (D3Rs), double 4-rings (D4Rs), and a new composite building unit [42.54.63]. D3Rs are very rare, previously only found in two zeolitic silicogermanates. ITQ-53 is stable up to at least 450 °C. The structure of ITQ-53 was changed from monoclinic to orthorhombic up on calcination.
IdentifiersURN: urn:nbn:se:su:diva-108927OAI: oai:DiVA.org:su-108927DiVA: diva2:761514