Study on preparation of rare earth enriched high-silica Y zeolite

High-silica Y zeolite (REGHSY) with RE₂O₃ content as high as 6-9% could be obtained by combination of SiCl₄ treatment and rare earth ion exchange. Comparing with REUSY prepared by hydrothermal method at similar unit cell size, the RE₂O₃ content of REGHSY was 3 times higher than that of REUSY. Therefore, the catalysts containing REGHSY zeolite exhibited higher cracking activity and hydrogen transfer activity. The samples were characterized by XRD, FTIR, aluminum-27 MAS NMA, and BET-N₂ adsorption. The difference of two preparation methods for increasing rare earth content was discussed based on the reaction mechanism and the preparation procedure. The keys of raising rare earth content were timely cleating out the extra-framework Si-AL species and keeping the channel of zeolite unblocked.