Photodegradation of an azo dye using immobilized nanoparticles of TiO2 supported by natural porous mineral.

Abstract Natural mordenite, replacing the synthetic zeolites, has been employed as the support of TiO 2 , and its photocatalytic activity has been examined in methyl orange (MO) aqueous under UV light. AFM, TEM, XRD, FTIR and fluorescence spectra have been used to reveal the loading effects of TiO 2 on mordenite. The results show that the photocatalytic degradation (PCD) reaction rates are sharply increased by natural zeolite supports. Since mordenite is photo-inert, the PCD-enhancement is mostly caused by the bonding effects of Ti–O–Si and Ti–O–Al. Moreover, another two distinct natural zeolites have been employed as the supports of TiO 2 , in order to check the universality of PCD-enhancement effect of natural zeolites on TiO 2 . And the factors of PCD reaction on TiO 2 –zeolite, such as pH and catalyst dose, have been investigated.