Beckmann rearrangement reaction: About the role of defect groups in high silica zeolite catalysts

The aim of this paper is to investigate the role played by the zeolitic defect groups on the catalytic behavior of Silicalite-1 in Beckmann rearrangement reaction. Samples of Silicalite-1 catalysts were prepared and activated by different post-synthesis procedures. Catalytic activity and deactivation rate of the different catalysts were correlated with the different types of hydroxyl population. FT-IR and NMR techniques were used in order to determine the amount of defect groups and the different silanol types. The results show that Silicalite-1 is a good catalyst for Beckmann rearrangement reaction and when the geminal silanols are present the catalyst deactivate faster.