Preparation and Performance Study of Waste Plastic Blended Ultrafiltration Membrane

Abstract

Waste plastic packaging bags (rPVC) and waste milk tea straws (rPLA) were used as membrane materials to prepare ultrafiltration (UF) membranes by the non-solvent phase method (NIPS). The study aimed to investigate the influence of various factors, including different rPVC contents (10wt%-20wt%), membrane fractions (rPVC/rPLA), additive fractions (Pluronic F-127/PVP-K30), and different additive contents (0.5wt%-3.0wt%), on the performance of the membranes. The permeability, morphology, hydrophilicity, chemical composition, thermal stability, and antifouling properties of the blended UF membranes were thoroughly investigated. The experimental results revealed that the presence of rPLA and Pluronic F-127 increased the porosity, water absorption, pore size, and hydrophilicity of the blended UF membranes. Furthermore, the introduction of rPLA enhanced the thermal stability of the blended UF membranes. Additionally, the incorporation of Pluronic F-127 further improved the overall performance of the blended UF membranes. Specifically, it was found that the blended UF membranes achieved a pure water flux (PWF) of 192.50L·m-2·h-1, while maintaining a bovine serum albumin (BSA) rejection rate of 95.20%. These results were obtained using a content ratio of rPVC/rPLA (90/10) at 14wt% and an additive content of Pluronic F-127 at 2.5wt%. By comparing with the blended UF membranes without introducing additives into the casting solution, the roughness (Ra) was reduced by 40.3%, the water contact angle (WCA) was reduced by 7.5%, the flux recovery rate (FRR) was increased by 80.5%, and the fouling resistance was enhanced.