Improvement of polyvinylidene fluoride membrane performance by combination of polyethylene glycol and dragon blood resin through coordination reaction with Fe3+ ions

Fouling on hydrophobic membranes can be eliminated by modification with hydrophilic additives such as dragon blood resin (DBR: bio-polymer) and polyethylene glycol (PEG: non-bio-polymer). In this study, the surface modification of polyvinylidene fluoride (PVDF) membranes with bio/non-bio polymeric additives and their coordination reaction with Fe3+ ions was investigated. Five types of membranes with different compositions were prepared by immersion precipitation phase inversion method. The result showed that membrane M–PD (PVDF/PEG/DBR) improved the membrane hydrophilicity, resulting in high pure water flux (98.7 L.m−2.h−1) and humic acid rejection (99.08 %). However, the coordination reaction with PEG and Fe3+ as well as PEG/DBR and Fe3+ resulted in reduced water and humic acid flux. Coordination reaction successfully increased membrane stability as evidenced by FRR < 100 %. These results will be useful in the design of PVDF-based membranes with bio- or non-biopolymer additives.