Immobilization of iron tetrasulfophthalocyanine on functionalized MCM-48 and MCM-41 mesoporous silicas: Catalysts for oxidation of styrene

Iron tetrasulfophthalocyanine (FePcS) has been anchored on the surface of functionalized MCM-48 and MCM-41 silicas by means of chemical bonding to ammosilane groups. The prepared materials, FePcS/NH2-MCM-48 and FePcS/NH2-MCM-41, were characterized by diffuse reflectance UV-vis and infrared (IR) spectroscopies, low-angle X-ray diffraction (XRD), and surface area analysis (BET). The tendencies of FePcS absorption on functionalized MCM-48 and MCM-41 were measured by UV-vis spectroscopy. The functionalized MCM-48 showed a larger amine to silica ratio than the functionalized MCM-41. Low-angle X-ray diffraction analysis showed that, by anchoring iron tetrasulfophthalocyanine into functionalized MCM-48 and MCM-41, the intensity of main reflection decreased. The catalytic activities of the supported iron tetrasulfophthalocyanine were examined by the oxidation of styrene in the presence of tert-butyl hydroperoxide. The FePcS/NH2-MCM-48 showed higher activity and durability in the liquid-phase oxidation of styrene under mild condition compared with the FePcS/NH2-MCM-41 and unsupported catalyst. (C) 2007 Published by Elsevier Inc.