纳米SiO2的加入对PVDF/SiO2超滤膜结构和性能的影响

将普通纳米SiO2、疏水纳米SiO2、亲水纳米SiO2分别加入到聚偏氟乙烯(PVDF)铸膜液中,通过相转化法制得PVDF/SiO2杂化超滤膜,重点探讨了SiO2加入量及上述三种类型纳米SiO2对PVDF杂化超滤膜水通量、截留率和抗污染性能的影响.结果表明:膜的孔隙率、平均孔径、水通量、截留率和抗污染性随SiO2含量增加而先增大后减少;SiO2含量为2%时,膜水通量由大至小为:普通纳米SiO2杂化膜、疏水纳米SiO2杂化膜、亲水纳米SiO2杂化膜,抗污染性由大至小为:亲水纳米SiO2杂化膜、普通纳米SiO2杂化膜、疏水纳米SiO2杂化膜.

Effects of the addition of nano-sized SiO2 on the structure and performance of PVDF/SiO2ultrafiltration membrane

The unmodified,hydrophilic and hydrophobic nano-sized SiO2 were added into the PVDF casting solution respectively,and the PVDF/SiO2 hybrid membranes were prepared by phase inversion method.The effects of SiO2 concentration and the above-mentioned three types of SiO2 on the PVDF membrane performances such as pure water flux,rejection ratio,anti-fouling capability were examined.The experimental results indicated that membrane porosity,mean membrane pore size,pure water flux,rejection ration,anti-fouling capability increased with rising SiO2 concentration firstly and then decreased.Besides,when the SiO2 concentration was 2%,in terms of pure water flux,unmodified nano-sized SiO2 hybrid membrane was the best,followed by hydrophobic nano-sized SiO2 hybrid membrane and hydrophilic nano-sized SiO2 hybrid membrane.Inversely,in terms of anti-fouling capability,hydrophilic nano-sized SiO2 hybrid membrane was the optimal,followed by unmodified nano-sized SiO2 hybrid membrane and hydrophobic nano-sized SiO2 hybrid membrane.