Study on the fouling behavior of HDPE/PE-g-MA/EVA blend membrane fabricated via thermally induced phase separation method

In this study, neat HDPE and HDPE/PE-g-MA/EVA blend membranes were fabricated via thermally induced phase separation (TIPS) method and their fouling behaviors were examined using filtration of BSA protein. Membranes were characterized using FESEM, AFM, ATR-FTIR analyses and porosity measurement. Fouling behavior of membranes was analyzed using the resistance-in-series (RIS), classic and combined pore blocking models. The results of RIS model revealed that the magnitude of inherent, reversible and irreversible resistances decreased from 0.611 ×1013m-1 and ,1.578 ×1013m-1 and 0.525 ×1013m-1 for the neat membrane to 0.237 ×1013m-1, 0.789 ×1013m-1 and 0.154×1013m-1 for the blend membrane, respectively. None of the classical Hermia’s models were able to accurately predict fouling during the entire filtration run. The results obtained from the combined pore blocking model indicated that the combined cake formation-intermediate blocking model provided good prediction of fouling mechanism for both the membranes. However, comparison between fitted parameters showed that much greater fouling occurred for pure HDPE membrane. The key reasons for such different fouling behaviors were mainly attributed to the difference in hydrophobicity as well as the distribution of pore size on the surface of the pure and blend membranes.