Photoinduced graft polymerization to improve antifouling characteristics of an SMBR

Hydrophobic polypropylene hollow fiber microporous membranes (PPHFMMs) were surface-modified by photoinduced graft polymerization of 2-aminoethyl methacrylate (AEMA), which were characterized by attenuated total reflection—Fourier transform infrared spectroscopy (FT-IR/ATR), X-ray photoelectron spectroscopy (XPS), and field emission scanning electron microscopy (FE-SEM). Water contact angle was measured by the sessile drop method. The results of FT-IR/ATR and XPS clearly indicated that AEMA was grafted on the membrane surface. The water contact angle on the modified membrane was 50.3° lower than that of the unmodified membrane. The antifouling characteristics in a submerged membrane bioreactor (SMBR) were investigated. After continuous operation in the SMBR for about 65 h, reduction from pure water flux was 3.03% lower, flux recovery after water and caustic cleaning were 28.01 and 48.95% higher for the AEMA grafted PPHFMM with a grafting degree of 5.67 wt.% than those of the unmodified membrane, flux ratio after fouling was 1.78 times for the modified membrane with a grafting degree of 7.30 wt.% of the unmodified one.