IDM-1: A Zeolite with Intersecting Medium and Extra-Large Pores Built as an Expansion of Zeolite MFI.

ABSTRACT

IDM-1 is a new silica zeolite with an ordered and well-defined framework constructed by alternating pentasil layers and interrupted layers, giving rise to an intersecting system of straight medium pores and undulating extra-large lobed pores. This unique structure was solved by rotation electron diffraction and refined against synchrotron powder X-ray diffraction data. Despite the presence of both Si(OSi)3 (OH) and Si(OSi)2 (OH)2 sites, this new zeolite presents high thermal stability, withstanding calcination even to 1000 °C. The location of defects at specific sites of the structure results in alternating hydrophobic SiO2 and hydrophilic SiO(2-x) (OH)2x intracrystalline regions. This peculiar combination of intersecting medium and extra-large pores and alternating regions of different chemical character may provide this zeolite with unique catalytic properties.