Characteristics and Preparation of PVDF Catalytic Membrane Modified by Nano-TiO2/Fe3+

ABSTRACT

The polyvinylidene fluoride (PVDF)/Fe3+-TiO2 catalytic membrane was prepared by sol-gel method. It was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR spectrum (FT-IR), mechanics capability, water flux, pepsin retention, porosity and contact angle etc. The catalytic activity of PVDF/Fe3+-TiO2 catalytic membrane was evaluated by the degradation of refractory dye Orange IV in the presence of H2O2. The results show that the addition of appropriate nano-sized TiO2 sol in the preparation of PVDF membrane has greatly improved some properties of the membrane such as microstructure, hydrophilic ability, mechanics intensity and water flux etc. The addition of Fe3+ ion in the preparation of PVDF membrane has greatly improved its catalytic activity to decompose H2O2. The catalytic activity of PVDF/Fe3+ -TiO2 is increased with the increase of the content of Fe3+ ion. When the content of Fe3+ _TiO2 sol is 21%, the content of Fe3+ ion is from 0.02% to 0.12%, the discolorization rate of Orange IV in this Fenton-like oxidation is from 61.2% to 90.5%. The catalytic activity of PVDF/Fe3+-TiO2 is not changed with the increase of the content of nano-sized TiO2. This kind of PVDF/Fe3+ -TiO2catalytic membrane has not only good filtration efficiency but also good catalytic activity to effectively decompose H2O2.

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