Synthesis and catalytic properties of titanium containing extra-large pore zeolite CIT-5

• Ti-CIT-5, a new extra-large pore titanosilicate was prepared and characterized.
• The lowest Si/Ti ratio in prepared material is 23.
• Ti-CIT-5 is active catalyst in epoxidation of olefins with H2O2.

Titanium containing extra-large pore zeolite CIT-5 (IZA code: CFI) was successfully prepared by direct synthesis using Cab-O-Sil M5 and titanium(IV) butoxide in the presence of LiOH. N-Methylsparteinium hydroxide was used as a structure directing agent. The product crystallized into thin plate crystals with an approximate size of 20 × 5 × 0.2 μm. The lowest achieved Si/Ti ratio was 23. The necessary duration of hydrothermal synthesis increased with increasing concentration of Ti in the reaction mixture from 11 days (Si/Ti = 63 in product) to 17 days (Si/Ti = 36) at 155 °C. Prepared Ti-CFI samples exhibit BET surface areas in the range of 308–346 m2/g and micropore volumes of 0.094–0.097 cm3/g. CFI possesses extra-large pores (14-ring, 7.2 × 7.5 Å) accessible for bulky molecules, therefore, Ti-CFI is a useful catalyst for epoxidation of double bonds in bulky molecules used in perfumery and pharmacy. The Ti-CFI samples proved to be catalytically active in epoxidation of 1-octene, cyclooctene, α-pinene, and norbornene with hydrogen peroxide as oxidation agent.

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