Ti-MCM-41 catalysts prepared by post-synthesis methods: Limonene epoxidation with H2O2

Ti-MCM-41 catalysts were prepared incorporating Ti by post-synthesis methods: wetness and wet impregnation of MCM-41 mesoporous solid. The samples were characterized by XRD at low angle, UV–vis DRS, Raman spectroscopy, BET, ICP and colorimetry. The results were compared with those obtained for Ti-MCM-41 hydrotermically prepared. All catalysts were tested in the limonene epoxidation with H2O2. Three kinds of Ti sites were observed in post-synthesis catalysts which were different from that found in the hydrothermal Ti-MCM-41. These structural differences do not produce important changes in the catalytic activity, instead a slight decrease in the epoxide selectivity can be observed. The catalysts prepared by post-synthesis methods are promising in the limonene epoxidation with H2O2 since these methods are simple and reproducible.