Composite photocatalytic membrane prepared by embedding porous SiO2 shell/void/TiO2 core particles into polycarbonate for photodegrading and removing pollutant from water

Abstract

In order to solve the problem of immobilizing and recycling TiO2 particles, the porous SiO2 shell/void/TiO2 core particles (SVT) were first prepared under the synergetic effect of oleic acid and non-ionic surfactant P123 to enhance light and mass transfer, and then embedded into polycarbonate to prepare composite photocatalytic membranes (CPMs). SVT were characterized by TEM while CPMs were characterized by FT-IR and SEM, showing that SVT were successfully synthesized and embedded into polycarbonate. Namely, the CPMs were successfully prepared. The optimum preparation conditions of CPMs were investigated and determined via porosity test of CPMs as follows: the content of PC, DMC and CH2Cl2 of the casting solution is 13wt%, 15wt% and 72wt%, respectively; the mass ratio of SVT/PC (g:g) is 1:1. The photocatalytic properties of CPMs were investigated through photodegrading methyl orange in water and oil in sewage containing oil, respectively. The results show that SVT have a porous structure, and CPMs have a better degradation rate for photodegrading methyl orange in water and oil in sewage containing oil, and the photocatalytic degradation rate does not decrease obviously after recycling many times, indicating CPMs possess better photocatalytic performance without degrading the polymer supports. The different cleaning methods of CPMs were also investigated to recover photocatalytic performance of recycled CPMs. Therefore, CPMs as a novel TiO2-immobilized structure will have a promising application in the immobilization and recycle of TiO2 catalyst with a better photodegrading and removing performance for pollutants from water.