Enhancing anti-fouling performance of ceramic membranes through iron oxide modification for the separation of oil-containing fermentation broth

Ceramic membranes are increasingly recognized for their effectiveness in processing fermentation broths. However, developing ceramic membranes with superior anti-fouling properties remains a challenge for large-scale applications. Iron oxide nanomaterials have gained significant research interest as a cost-effective and readily available solution for mitigating membrane fouling, thanks to their excellent hydrophilicity. This study introduces ceramic membranes enhanced with iron oxide via a facile sol-gel technique. The membrane's resistance to fouling, hydrophilicity, adhesion force, and surface potential were assessed. Post-modification, a consistent distribution of iron elements on the membrane surface was achieved, with negligible alteration in pore size. Although the pure water permeance (450 ± 45 L m⁻² h⁻¹·bar⁻¹) did not change significantly, the permeance of the modified membrane (225 L m⁻² h⁻¹·bar⁻¹) was nearly 20 % higher than that of the original membrane when separating a 1000 ppm oil-in-water emulsion, with both membranes achieving 99 % oil droplet rejection. Moreover, the flux recovery rate of the modified membrane surpassed that of the original membrane by approximately 30 %, indicating a significant improvement in anti-fouling performance. Upscaling experiments further validated the modified membrane's anti-fouling performance and capability to rapidly process broths with high oil content. Overall, this study presents a novel anti-fouling ceramic membrane for the treatment of oil-containing fermentation systems.