Highly-selective hybrid ultrafiltration membranes with AlPO4-5 zeotype fillers: Effect of filler loading, morphology, and metal substitution on performance and fouling resistance

In recent years, membrane technologies have emerged as a promising solution for water treatment, particularly ultrafiltration. However, fouling remains a significant challenge in membrane applications, leading to a decline in membrane performance over time. To address this issue, the development of antifouling membranes has garnered considerable attention. By tuning their hydrophilicity, roughness, and surface charge, such membranes aim to mitigate fouling effects and extend their operational lifespan. In this work, aluminophosphate zeotype AlPO4-5 and cobalt-substituted AlPO4-5 (CoAPO-5) fillers were hydrothermally grown, their physicochemical, structural, and morphological characteristics were evaluated, and both types of fillers were incorporated into polyethersulfone (PES) membranes via phase inversion to fabricate antifouling hybrid ultrafiltration membranes. Fabrication of PES/xCoAPO-5 (y) hybrid membranes (x: Co/Al2O3 mole%, y: H2O/Al2O3 molar ratio in the synthesis mixture of the zeolite synthesis) was realized by varying the loading of the zeolite in the casting solution. Water permeance and bovine serum albumin (BSA) rejection of the developed hybrid membranes were significantly enhanced depending on the metal content, filler morphology, and loading within the membrane matrix. The maximum water permeance (688.8 L m- 2 h-1 bar-1) was obtained for the membrane loaded with 6 wt% AlPO4-5 (400), which was 66 % higher than the pristine one, while a superior BSA rejection rate of 99.4 % was obtained from the membrane loaded with 6 wt% of 5CoAPO-5 (400).

Automated summary

In recent years, membrane technologies, particularly ultrafiltration, have emerged as a promising solution for water treatment. However, fouling remains a significant challenge in membrane applications, leading to a decline in membrane performance over time. To address this issue, the development of antifouling membranes has garnered considerable attention.