A reproducible, scaleable synthesis of ZSM-10 is reported. This synthe
sis is dependent on the presence of 1,4-dimethyl-DABCO cations during
the nucleation/aging stage, but this directing agent is not incorporat
ed in the final product. Analysis of the zeolite product during aging
shows that offretite is formed first and then converts to ZSM-10. The
framework topology of ZSM-10 (K24Al24Si84O216 . xH(2)O . yR) has been
determined from synchrotron X-ray and electron diffraction data, model
building, and X-ray powder pattern simulation, ZSM-10 has a large hex
agonal unit cell with a = 31.575(7) Angstrom, c = 7.525(4) degrees, PG
/mmm maximum topological symmetry, and a tetrahedral framework density
of 16.6 T/1,000 Angstrom(3). The tetrahedral framework is constructed
from columns of alternating cancrinite cages and double 6-rings which
also build the LTL (Linde Type L or zeolite L) and OFF (offretite) fr
ameworks. Two different one-dimensional, 12-ring pore systems parallel
the c axis in ZSM-10. One 12-ring channel is topologically identical
to the undulating channel in the LTL framework, and the other is ident
ical to the 12-ring channel in the:OFF framework. ZSM-10 appears to be
the first zeolite with two distinct, parallel, 12-ring channel system
s that occur individually in other zeolites.