Synthesis of comparable Co-MCM-48 and Co-MCM-41 materials containing high cobalt contents

By a new procedure, Co-MCM-48 and Co-MCM-41 samples have been synthesized with up to 2.5 wt% Co incorporated into the framework. The charge density matching process has been found to be dependent upon the pH in the gel, due to the different solubility of different silica species. By controlling this silica chemistry and also the interfacial chemistry of cobalt during incorporation, the obtained structure and cobalt content of the synthesized materials may be simultaneously controlled. Sodium silicate has been used as the silicon source, which allows for variable amounts of ethanol to be added to the gel, thereby controlling the surfactant packing parameter. Following this approach, Co-MCM-41 and Co-MCM-48 samples with high cobalt contents have been prepared from similar synthesis gels. Due to the similar synthesis conditions, the surface properties of these samples are similar, which may make them well-suited for application as comparable materials in catalysis or adsorption model studies.