Effective hierarchization of TS-1 and its catalytic performance in cyclohexene epoxidation

• Very open porous structure provided improved catalytic activity of mesoporous TS-1.
• Applied leaching conditions guarantied the retaining of Ti4+ in tetrahedral positions.
• Preserved microporous characteristics of mesoporous TS-1 by CH3OH/alkaline medium usage.

The presented data showed that the chemical treatment of TS-1 with alkaline medium resulted in the formation of highly developed hierarchical structures. The esterification of the hydroxyl groups by methanol allowed modifying the hydrophobicity of TS-1 surface and obtaining truly micro/mesoporous material. The preservation of microporous characteristics was confirmed by XRD and low temperature nitrogen sorption studies. Detailed information on acidic properties of mesoporous titanosilicalites was delivered by IR studies of pyridine sorption and implicitly from 29Si MAS NMR investigations. Well-developed internal mesoporosity together with the retaining of Ti4+ atoms in tetrahedral framework positions offered 7-fold higher catalytic activity for the conversion of cyclohexene molecules than the native microporous TS-1. The selectivity to epoxide reached the value of 96% for the most efficient mesoporous titanosilicate.

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