Solution - phase grafting of Pd/PdO onto the pore surface of MCM - 41 mesoporous molecular sieves

Pd/PdO, a versatile catalyst, has been grafted onto the pore surface of MCM - 41 by reacting PdCl ₂ solution with the as - synthesized mesostructured aluminosilicate. The products have been characterized by powder XRD, thermal analysis (TG/DTA) , TEM, N ₂ adsorption and FT- IR spectroscopies. It was found that palladium is loaded onto the aluminosilicate walls via Si - O - Pd bonds. A second phase consisting of Pd/PdO crystallites ranged from 10 to 30nm in diameter on the external surface of the mesoporous aluminosilicate materials was obtained. It is concluded that clogging of channels with Pd/PdO is avoided by introducing the reagent when surfactant is still present in the mesopores.