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 degrees 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. (c) 2007 Elsevier B.V. All rights reserved.