Fabrication and Performance Evaluation of PVDF/Nano-TiO₂ Membrane via NIPS Method for Tetracycline Removal Using Vacuum Filtration.

Abstract

Water pollution caused by tetracycline contamination is a serious issue due to its poor biodegradability and potential to trigger antimicrobial resistance. This study aims to evaluate the filtration performance (permeate flux and rejection efficiency) of a PVDF membrane modified with 10% nano-TiO₂ fabricated via non-solvent induced phase separation (NIPS) under vacuum filtration for tetracycline removal. Polyvinylidene fluoride (PVDF) membranes modified with 10% (wt) nano-TiO₂ were cast using the NIPS method and processed using a vacuum filtration system at 200 mbar. The incorporation of nano-TiO₂ may improve membrane hydrophilicity and pore formation, as indicated by SEM morphological changes and supported by previous studies. The morphology exhibits a distinct asymmetric structure, consisting of a thin, dense upper layer and a lower layer dominated by sponge-like pore structures. The modified membrane demonstrated a very high permeate flux ranging from 312.5 to 8,375.2 L·m⁻²·h⁻¹·bar⁻¹, while tetracycline rejection ranged from 29.31% to 55.81%. The high flow rate indicates that the system can manage wastewater contaminants on a large scale. However, further optimization of the molecular sieve separation system is required to improve rejection. Overall, PVDF modification with nano-TiO₂ has proven effective in boosting filtration productivity and holds potential for treating tetracycline-contaminated wastewater.