Constructing PTFE-ZrO₂ hybrid membrane with tailored surface energy for enhanced anti-fouling performance

The presence of biological substances and organisms on the membrane surface poses a significant challenge in the downstream process of biomass separation using membrane technology. Current strategies to address this issue involve designing special surfaces with either hydrophilic groups or low surface energy compounds. In this study, we prepared a hybrid membrane with unique surface energy by integrating polytetrafluoroethylene (PTFE) nanoparticles with zirconia (ZrO₂) nanocrystalline. By optimizing the volume ratio of PTFE to ZrO₂ at 1:3, the surface energy of the hybrid membrane was reduced to an appropriate range, effectively reducing microbial adhesion in the fermentation broth. Additionally, it harnessed the capability of ZrO₂ nanocrystalline to form small pores, thereby reducing protein blockage and adsorption, which alleviated membrane fouling in the fermentation broth. This dual-defense mechanism significantly enhanced the stable flux of the hybrid membrane in real ethanol fermentation broth, exceeding that of the ceramic substrate by 2.1 times, with a flux recovery ratio of 95.5%. These results broaden the application prospects of hybrid membranes to perform clarification and recovery of biobased products from fermentation broth.