Synthesis of the Zeolites from SBU: An SSZ-13 Study

Zeolite SSZ-13 was successfully synthesized via interzeolite conversion of zeolites X, A, and ZSM-5. Si(4Al) and Si(1Si, 3Al) were monitored by 29Si MAS NMR spectroscopy and together with the ion exchange capacity to Co(II) ions were employed to monitor secondary building units (SBU) and (SiAl)n sequences transferred from parent X and A zeolites to the structure of SSZ-13. The starting material serves as an Al and partial Si source and has to be disintegrated into linear or branched (SiAl)n sequences. Also, no mutual structural building units, e.g., hexagonal prisms or 6 rings, are required for the formation of SSZ-13 zeolite. Among transferred (SiAl)n sequences, a significant fraction (ca. 45%) is relocated in the form of chains with at least five T atoms containing three Al atoms (AlTRI), decreasing the ion exchange capacity as only two of the three Al atoms are involved in balancing one Co(II).