A review on microporous polyvinylidene fluoride membranes fabricated via thermally induced phase separation for MF/UF application

To date, remarkable success has been achieved in the fabrication and industrialization of poly(vinylidene fluoride) (PVDF) membranes both in lab-scale and full-scale via thermally induced phase separation (TIPS) method for microfiltration/ultrafiltration (MF/UF) applications in water treatment. This article provides a comprehensive and heuristic overview of the fabrication, development, and industrialization of PVDF microporous membranes via TIPS during the recent several decades. Firstly, detailed information about the PVDF material was given to illustrate why PVDF was widely considered as a prominent material and how to choose a suitable polymer raw material for membrane production. Then from a historical developing perspective, this paper reviewed two commonly applied preparation methods for PVDF microporous membranes and highlighted the advantages of the TIPS method. Thirdly this work presented a deep review on the fast development of PVDF membrane fabrication and modification to show how to prepare and improve the polymeric microporous membranes via TIPS, following a line of thermodynamic formula design, experimental kinetics study, dynamic analysis of the preparation process based on modeling and simulation methods, and hydrophilic modification analysis based on an industrial and application perspective. Next based on the production and application status of present worldwide commercial PVDF membrane manufacturers, we summarized vital challenges to realize industrial-scale fabrication and extensive MF/UF applications for PVDF membranes via TIPS, and then aiming at the urgent issues to be addressed during the membrane application, some emerging advanced techniques based on TIPS were introduced to point out the next possible method for realizing commercialization. Finally, conclusions and future challenges are presented. This paper provides new insights about polymeric membrane fabrication and industrialization via TIPS from technology development and membrane application perspectives.