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To investigate the effect of hydrophobic and hydrophilic polypropylene hollow fiber membranes (PPHFMs) applied in membrane bioreactors (MBR), the fouling behaviors of membrane surfaces and pores have been tested. The structural and morphological features on the membrane surface were characterized using attenuated total reflection-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, atomic force microscope, energy dispersive X-ray spectroscopy and laser granularity distribution analysis. The results showed that significantly more polysaccharide, protein and inorganic ingredients were accumulated in the original membrane compared to the hydrophilic membrane. Furthermore, it was found that the pore size influenced the particle distribution and accumulation, such that smaller pore size membranes tended to contain fewer pollutants and a narrow size distribution. Under a constant flux of 11.5 L/m2 h, the transmembrane pressure (TMP) varied narrowly between 38 and 53 KPa....

The polypropylene (PP) fibers were chosen as substrate materials. Functional fibers containing iron were prepared by UV irradiation-coordination method, and then Pd/Fe bimetallic composite catalytic fibers were prepared by replacement reaction and used for the removement of N-nitrosodimethylamine (NDMA). The effect of monomer concentration, the pH of the reaction system and reaction temperature on NDMA catalytic degradation was investigated. The results indicate that the degradation rate of NDMA can reach 69.97% when the AA monomer concentration is 20%, which is the best catalytic reduction effect of composite catalytic fiber on NDMA. The pH of solution and reaction temperature can not greatly influence the catalytic reduction of NDMA.

In this work, an acrylic-polypropylene grafting copolymer (PP-g-AA) was prepared by 60Co γ-rays irradiation grafting with acrylic acid (AA) onto polypropylene (PP) fiber. The esterification PP-g-AA fiber (PP-g-COOR) was prepared by the esterification of PP-g-AA with C8 alcohol via SOCl2 as the intermediate. The PP-g-COOR fiber was utilized to adsorb and enrich trace dibutyl phthalate (DBP) in water. The results indicated that PP-g-COOR fiber exhibited a good adsorption property of DBP. The adsorption property of PP-g-COOR fiber was greatly enlarged 25 times than the PP-g-AA. The distribution coefficient of DBP on PP-g-COOR fiber depended on the pH values of aqueous phase and the initial concentration of DBP. In general, the PP-g-COOR fiber was better for the adsorption and enrichment of DBP.

A weak acid cation exchange fiber was prepared by γ-ray pre-radiation induced grafting of acrylic acid (AA) onto polypropylene (PP) non-woven without removal of the polymerization inhibitor in acrylic acid. The factors influenced the grafting degree were discussed, such as radiation dose, initiator concentration, monomer concentration, storage time and bath ratio. It is found that the initiator 2, 2'-Azobisisobutyronitrile (AIBN) was necessary for the increased grafting of AA without removing the inhibitor in AA.

The purpose of this paper was to evaluate the capacity of anion ion exchange fiber to uptake the heavy metal(Co2+、Cu2+、Zn2+、Cd2+、Pb2+、Ag+) from the water. A new polyamine-type ion exchange fiber(IEF) based on polyacrylonitrile (PAN) with higher exchange capacities was prepared by crosslinking through hydrazine hydrate, followed reacting with diethylene triamine. FT-IR analysis indicated that amine, imido, acylamino and carboxyl groups were introduced into PAN fiber through the surface modified reaction of cross linking and amination. The structures of the IEF were characterized by means of SEM. The results showed that the surface of fiber became rougher and thicker and more heterogeneous. The static and dynamic adsorption experiments demonstrated the high selective adsorption property of the IEF for Ag+ and Cu2+. Furthermore, the adsorption mechanism for the metal ions with IEF was investigated with the FT-IR spectra studies.

A novel type of weakly acidic cation exchange fiber have been prepared by 60 Co irradiation grafting with acrylic acid onto the polytetrafluoroethylene (PTFE) fiber. The exchange capacity of the grafted fiber is 3.06 mmol/g. The pH titration curve of the grafted fiber showed there is a sudden jump when pH is round 6–10, and the acidity of the grafted fiber is stronger than that of commercial weakly acidic exchange D-152 resin. The grafted fiber showed the excellent selectivity of static and dynamic adsorption for Cu 2+ , La 3+ and Pb 2+ when Mg 2+ , Ca 2+ , Cr 3+ , Co 2+ , Ni 3+ , Cu 2+ , Ag + , La 3+ , Pb 2+ were coexisted. The grafted fiber could be regenerated completely with almost equimolar diluted hydrochloric acid.