NaY zeolite consists of the supercage, sodalite cage and the hexagonal prism. It is generally believed that a major fraction of the ion exchanged Fe2+ cations is in the hexagonal prism and part of the Fe2+ cations is in the sodalite cage [23]. In the present study, these exchanged Fe2+ ions acted as seeds for the growth of Fe0. The formation of dispersed nano-Fe0 led to an increase in the number of active sites for the heterogeneous Fenton reaction. On the other hand, NaY zeolite has a Lewis acid character [24].