Preparation and characterization of a novel hydrophilic PVDF/PVA/Al2O3 nanocomposite membrane for removal of As(V) from aqueous solutions

摘要

In this study, the novel Poly(vinylidene fluoride)(PVDF)/polyvinyl alcohol (PVA)/Al2O3 nanocomposite blend membranes with hydrophilic surface were prepared for the first time and used for removal of Arsenic from aqueous environments. First, PVDF/PVA blend membranes were prepared via Non-solvent-Induced Phase Separation method and then the characterization was done by several methods. Presence of PVA in membrane matrix caused significant improvements in hydrophilicity and permeability. Although the water contact angle was about 86 degrees for the pure PVDF membrane, it reduced to about 44 degrees for the membrane with the highest PVA content (PVDF/PVA mass ratio = 92/8). Based on the results of the scanning electron microscopy analysis, contact angle measurements, permeability (pure water permeation flux), and tensile strength tests the membrane with PVDF/PVA ratio of 96/4 was selected as the base membrane; thereafter, Al2O3 nanoparticles with weight percents of 1-to 5% (with respect to total polymer weight) were added to the casting solution of the aforementioned blend membrane. The resulted nanocomposites were evaluated through further experiments such as energy dispersive X-ray spectroscopy analysis, attenuated total reflectance-fourier transform infrared (ATR-FTIR) spectroscopy, and Arsenic rejection test. The results showed that removal efficiency was directly dependent on Al2O3 concentrations in membrane's matrix so that it soared to 90% for the membrane including 5% of Al2O3. Besides increase in hydrophilicity and permeability, adding nanoparticles also caused significant improvements in mechanical properties of the prepared nanocomposite membranes. POLYM. COMPOS., 40:2452-2461, 2019. (c) 2018 Society of Plastics Engineers