Iron phthalocyanine supported on silica or encapsulated inside zeolite Y as solid photocatalysts for the degradation of phenols and sulfur heterocycles

The photocatalytic activity of iron phthalocyanine adsorbed on silica (FePc/SiO2) or encapsulated within NaY zeolite (FePc@NaY) towards the degradation of two model compounds using hydrogen peroxide as oxidant has been determined. It was found that while FePc/SiO2 exhibits higher intrinsic activity than FePc@NaY for the degradation of phenol in water, FePc/SiO2 cannot be used as heterogeneous photocatalyst in organic solvents due to self-degradation and/or desorption of the iron phthalocyanine from the silica surface to the solution. Thus, for the oxidative photodegradation of benzothiophene in acetonitrile using FePc/SiO2 as photocatalyst (a model reaction with importance in the fuel industry), the silica becomes colorless and without possibility of reuse. In contrast, FePc@NaY, in where iron phthalocyanine is permanently immobilized inside the zeolite pores, can be recovered by filtration after the photodegradation of benzothiophene in acetonitrile and reused. (c) 2004 Elsevier B.V. All rights reserved.