Eco-friendly membrane fabrication from polystyrene waste: A circular economy perspective

This study optimized the manufacturing process of a membrane derived from polystyrene waste for application in a membrane bioreactor for wastewater treatment by adjusting parameters including resin-to-solvent ratio, coagulation time, and membrane thickness. The research results showed that polystyrene plastic demonstrated compatibility with N-Methyl-2-pyrrolidone solvent at a resin-to-solvent (m/V) ratio of 4:25. The ideal coagulation time was found to be 20 min and a thickness of 350 µm. The MBR tank employed a frame of flat sheet membranes made from polystyrene waste with consistent performance throughout the entire operation. On average, it achieved an 80% removal efficiency for COD, 94% for ammonium, and 8% for phosphate and turbidity of 1.5 NTU. These obtained results confirmed that membranes made from plastic waste could be effectively used in a membrane bioreactor (MBR) system for domestic wastewater treatment. Therefore, recycling polystyrene waste as a primary resource for membrane production is a viable concept for both technical and environmental purposes, promoting sustainable growth in the context of a circular economy.