Synthesis and Characterization of Low Aspect Ratio CrCoAPO-5 Molecular Sieves

The crystal morphology and size of CrCoAPO-5 molecular sieves were regulated by controlling gel preparation temperature and crystallization rate. The synthesized molecular sieves were characterized by SEM,XRD, FT-IR, UV-vis, TG, BET and ICP-OES. It was shown that hexagonal plate-like CrCoAPO-5 molecular sieves could be synthesized by conventional hydrothermal crystallization at 150 ℃ for 4.5 h through introducing seeds into the synthetic gels that were prepared at 5 ℃. The 3 μm-sized CrCoAPO-5 crystals with the aspect ratio less than 0.2 could be obtained, resulting in shorter diffusion distance and better catalytic activity compared with larger ones.