The use of MCM-22 as catalyst for the Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam

Abstract

A variety of catalysts have been applied to the Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam. Experiments with MFI structures yielded good results showing the importance of weak acidic sites, a large outer surface and pore structure accessible only through 10 MR channels. Recent reports on the discovery and characterisation of the MCM-22 catalyst with its large outer surface and special structure recommended this material for the use in the Beckmann rearrangement. In the present study the synthesis and brief characterisation of MCM-22 was carried out followed by the first in depth analysis of its applicability for the Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam. The performance of the material was compared to one of the established catalysts, the [B]-MFI, showing several drawbacks like lower yields and poor mechanical stability.