【摘要】 以筛孔75μm涤纶网为基衬,N,N-二甲基甲酰胺、丙酮为混合溶剂(质量比8:2),采用静电纺丝法制备了PVDF-HFP/Si NPs疏水复合膜,考察了疏水气相纳米Si O2颗粒(Si NPs)对纳米纤维膜结构及性能的影响。结果表明,随着纺丝液中Si NPs含量的增加,其红外特征吸收峰将愈发明显;膜厚度上升,而孔隙率却随之降低;尽管加入Si NPs后,膜的平均孔径变大,但膜表面疏水性的提高则保障了复合膜在膜蒸馏过程中仍可保持优异的截留性能。以质量浓度35 g/L的Na Cl溶液为进料液进行直接接触式膜蒸馏脱盐实验,当进料温度和渗透温度分别为53℃和20℃时,各复合膜盐截留率均能达到99.99%以上,膜通量可达12.0 kg/(m2·h)。更多还原

【Abstract】 Poly(vinylidene fluoride-co-hexafluoropropene)/Silica nanoparticles(Si NPs) composite membranes were prepared by electrospinning method,which used polyester meshes with 75 μm sieve pore as support layer, and mixed of N, N-Dimethylformamide(DMF) and acetone(mass ratio was 8:2)was selected as solvent. The effect of Si NPs on the morphology and properties of the composite membrane was investigated. The results showed that, the infra-red spectrum absorption peaks of the Si NPs would become more significantly, and the thickness of the composite increased with the Si NPs content increasing in the polymer dope, but the membrane porosity decreased. Although the mean pore size of the composite membrane got larger with the Si NPs addition, the stronger hydrophobic surface of the composite membrane helped to maintain high salt rejection during membrane distillation process. 35g/L Na Cl solution was used as the feedstock to test the direct contact membrane distillation desalination experiment, when feed and permeate temperature was 53 ℃ and 20 ℃ respectively, salt rejection of each composite membrane could reach above 99.99% and membrane flux could reach 12.0 kg/(m2·h).更多还原