Access to clean and safe water is paramount as the global population increases. However, industrial and agricultural runoff introduce heavy metals into water sources. Adsorptive membranes have been investigated as a potential water treatment method to remove these ions from drinking water. Compared to traditional separation methods such as nanofiltration and packed beds, absorptive membranes offer low energy requirements, high permeability, and high selectivity advantages. This study explores the impact of fabrication conditions on membrane structure and heavy metal ion removal. Membrane fabrication occurs via surface-segregation and vapor-induced phase separation (SVIPS), and utilizes the interaction of the polymer, solvent, and non-solvent. Polysulfone (PSF) and polystyrene-b-poly(acrylic acid) (PS/PAA) are dissolved in 2-pyrrolidone (2P), the solution is cast on a glass substrate, and humid air intrudes into the membrane. The intrusion stage leads to the formation of the membrane’s porous structure and facilitates water flow across the membrane. The membrane is placed in a DI water bath to vitrify. The fabrication conditions, such as polymer concentration, casting time, humidity, and annealing, can influence the nanostructure, throughput, and adsorption efficiency of the membranes. Scanning electron microscopy (SEM) and hydraulic permeability testing are used to characterize membranes. The membrane’s copper adsorption capacity is measured using ICP-OES. Preliminary results show that either annealing the membrane or increasing the PS/PAA concentration decreases permeability. These modifications to the casting process present an opportunity to optimize the performance of polysulfone-based membranes based on target contaminants and functionalized ligands such as terpyridine (TeRP) and polyethylenimine (PEI).
