Dependence of the structural stability of MCM-41 on the impregnating iron solution

The MCM-41 mesoporous material was chosen as support of very small iron oxide particles. To study the preparation conditions that allow to preserve the support structure four samples were prepared. The solids were characterized by atomic absorption spectroscopy (AAS), specific surface area (BET), X-ray diffraction (XRD) and Mossbauer spectroscopy at 298 and 22 K. The absence of water in the impregnation step is essential to avoid the collapse of the structure.