Unveiling the mechanism of enhanced water purification by F-Fe-Zn-MCM-41 in O3/PMS

Abstract

To break the restriction of SO52- as the essential initiator in O3/PMS reaction during water purification, F-Fe-Zn-MCM-41 (FFeZn-M) was designed to enhance ibuprofen (IBP) degradation during O3/PMS process. The great electronegativity difference between Fe and Zn created an electron flow from Zn to Fe, which was further enhanced by electron withdrawing Si-F group. FFeZn-M changed the traditional interaction between PMS and O3. PMS would be adsorbed on the surface of Zn and acted as an electron donor. Meanwhile, O3 received electrons from Fe site and was activated into ROS. With •OH and 1O2 as the main ROS, FFeZn-M/O3/PMS process achieved the complete IBP removal and a 60.9% mineralization rate, which was significantly higher over those of FFeZn-M/O3 and FFeZn-M/PMS processes. FFeZn-M/O3/PMS behaved better at weak acidic and neutral condition rather than the basic condition required by conventional O3/PMS process. This study offered a novel catalyst design strategy for O3/PMS.