Modifying the hydrophilic properties of polymeric hollow fiber membranes used for refinery wastewater treatment

To address the low permeability and high fouling of pure PAI membranes, this study fabricated hydrophilic PAI/CA hollow fiber membranes via a wet-dry spinning process for complex industrial effluent treatment. The incorporation of CA significantly modulated the membrane’s properties. Specifically, an 85/15 PAI/CA ratio increased surface hydrophilicity, reducing the water contact angle from 71.4° to 42°. Although this improvement led to a reduction in mechanical integrity with burst pressure decreasing from 850 kPa (pure PAI) to 700 kPa (85/15 PAI/CA) it markedly enhanced performance. The 85/15 membrane exhibited the highest permeation flux due to increased porosity and reduced hydraulic resistance. Furthermore, CA incorporation improved long-term stability; after 200 minutes, the flux decline was only 30% for the 85/15 membrane, compared to 40% for pure PAI. These findings demonstrate that blending CA is an effective strategy to optimize permeability and anti-fouling resistance, providing a robust solution for industrial wastewater reclamation despite the trade-off in mechanical strength.