Al2O3/poly acrylonitrile nanocomposite membrane: from engineering design of pores to efficient biological macromolecules separation

The main purpose of this research is to use aluminum oxide nanoparticles in order to manipulate the formation mechanism of poly acrylonitrile (PAN) UF membranes with the aim of improving their performance in separating biological macromolecules including sodium alginate, humic acid, bovine serum albumin (BSA). For this purpose, alumina nanoparticles with the approximate size of 40 nm and high hydrophilicity properties were placed within the structure of the PAN membrane to engineering design of pores. Viscometry analysis and determination of cloud point were performed in order to investigate the formation mechanism of the nanocomposite membrane. Chemical, surface, and morphological variations of the nanocomposite membrane were evaluated using FTIR, zeta potential, contact angle, DLS, porosity metering, SEM, and AFM analyses. Eventually, investigation of the filtration performance of the nanocomposite membranes showed that the membranes containing 1 wt% of alumina nanoparticles have a water flux 57% more than that of raw membrane. Further, in terms of flux recovery parameter, this membrane indicated 22, 9, and 14% increase for sodium alginate, humic acid, and BSA, respectively. Regarding extent of dye separation, sodium alginate separation, humic acid separation, and BSA separation, 12, 7, 9, and 7% increase was observed for the nanocomposite membrane containing 3 wt% of alumina nanoparticles.