Beckmann rearrangement of cyclohexanone oxime over Hβ zeolite and Hβ zeolite-supported boride

Hβ was synthesized by a hydrothermal method followed by ion exchange and used as support for the preparation of a Hβ zeolite-supported boride by impregnating H3BO3. The two catalysts were characterized by BET surface area measurement, XRD, IR, pyridine-TPD, etc. and studied in the Beckmann rearrangement of cyclohexanone oxime. In comparison with pure Hβ, the loadings of 9.09 wt% B2O3 lead to lower BET area, more total acid sites, more weak acid sites, especially more weak Brønsted acid sites, and slow deactivation in the Beckmann rearrangement. The results indicated that for the catalysts having the structure of β zeolite, the suitable acid sites for the Beckmann rearrangement might be weak Brønsted acid.