The removal of bisphenol A (BPA) by hollow fiber of microfiltration membrane

The removal of bisphenol A (BPA) from drinking water by hollow fiber of microfiltration membrane (MF) using dead-end model was investigated. The experiment was focused on the effect of various factors including BPA initial concentration, pH, ionic strength and organic matter on removal efficiency. The results showed that MF could remove BPA effectively. A higher removal was obtained at the beginning of the filtration, the removal efficiency decreased to around 20% when the membrane became saturated, due to adsorption of BPA onto the MF membrane. As pH of solution approached to pKa (9.6-11.3) of BPA, BPA removal efficiency dropped significantly. The effect of ionic strength on BPA removal was negligible. The adsorption plays a significant role in BPA removal in MF filtration. The influence of natural organic matter on BPA removal was positive or negative depending on competition or interaction between BPA and membrane play its role. The backwash could recover removal efficiency effectively.

In this experiment, BPA removal using MF hollow fiber membrane was investigated. The experiment was focused on the effect of various factors on BPA removal with respect to BPA initial concentration, pH, ionic strength and organic matter. The obtained results are summarized as follows: （1）When BPA initial concentration was unchanged, no significant effect on BPA removal was found. However, with BPA initial concentration was changed, significant effect on BPA removal was observed, suggesting that BPA absorption onto MF membrane was reversible. （2）As pH values closed to pKa of BPA, BPA removal was substantially decreased from around 70% at 3.32 pH and 7.00 pH to 30% at 10.01 pH and 11% at 11 pH. （3）No influence of Ca2+ on BPA removal was observed. （4） BPA removal by MF membrane can be attributed to adsorption mechanism.