title: Enhancement of the flux for polypropylene hollow fiber membrane in a submerged membrane-bioreactor by surface modification.
abstract: To improve its limiting flux and antifouling characteristics in a submerged membrane-bioreactor (SMBR) for wastewater treatment, polypropylene hollow fiber microporous membrane (PPHFMM) was surface-modified by the plasma-induced immobilization of poly (N-vinyl-2-pyrrolidone) (PVP) and the plasma treatment with different gases respectively. Attenuated total reflection-Fourier transform infrared spectroscopy (FT-IR/ATR), X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscope (FE-SEM) were used to characterize the structural and morphological changes on the membrane surface. Water contact angle was measured by the sessile drop method. It was found that the water contact angle was 128.8, 72.3, 62.7, 74.4, 79.1, 86.3, and 71.3 degrees for the nascent, PVP-immobilized, air, O2, Ar, CO2 and H2O plasma treated PPHFMM, respectively. The SMBR was operated at fixed transmembrane pressure to determine the limiting flux for the PPHFMM before and after surface modification. Results showed that the limiting flux appeared to be 103, 159, 117, 133, 136, 121 and 152 L/(m(2)x h) for the nascent, PVP-immobilized, air, 02, Ar, CO2 and H2O plasma treated PPHFMM, respectively. After continuous operation for about 50 h in the SMBR, the antifouling characteristics were improved to some extent.
authors.affiliation: Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education of China, Institute of Polymer Science, Zhejiang University, Hangzhou 310027, China. yuhaiyin@126.com
authors.forename: Hai-yin
authors.initials: HY
authors.lastname: Yu
authors.forename: Hao
authors.initials: H
authors.lastname: Lei
authors.forename: Zhi-kang
authors.initials: ZK
authors.lastname: Xu
mesh_terms: D019149:Bioreactors; D008567:Membranes, Artificial; D008855:Microscopy, Electron, Scanning; D011126:Polypropylenes / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry; D011759:Pyrrolidines / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D014865:Waste Disposal, Fluid / Q000295:instrumentation*
chemical_list: D008567:Membranes, Artificial; D011126:Polypropylenes; D011145:Polyvinyls; D011759:Pyrrolidines; C505150:poly(N-vinylpyrrolidine)