• Title/Summary/Keyword: nanofiltration membrane

Search Result 192, Processing Time 0.028 seconds

Preparation of poly(vinyl alcohol)-coated Composite Nanofiltration Membranes on Various Support Membranes (다양한 지지체 분리막 위에 poly(vinyl alcohol)이 코팅된 나노복합막의 제조)

  • Lee Kew-Ho;Kim In-Chul
    • Membrane Journal
    • /
    • v.15 no.1
    • /
    • pp.34-43
    • /
    • 2005
  • The poly(vinyl alcohol) (PVA)-based thin film composite nanofiltration (NF) membranes were prepared by coating polysulfone ultrafiltration membranes, sulfonated polyethersulfone and polyamide NF membranes with aqueous PVA solution by a pressurizing method. The PVA was cross-linked with aqueous glutaraldehyde solution. The NF membranes coated with a very low concentration of PVA on all the support membranes was successfully prepared. With increasing the hydrophilicity of the support membranes, the water flux increased. Especially, ζ-potential of negatively charged polyamide NF membrane was reduced by coating the membrane with PVA. A fouling experiment was carried out with positively charged surfactant, humic acid, complex of humic acid and calcium ion and bovine serum albumin. A non-coated polyamide NF membrane was significantly fouled by various foulants. The fouling process when using humic acid and protein occurred at the isoelectric point. There was severe fouling when using humic acid and adding bivalent cations. By coating the polyamide NF membrane with aqueous PVA solution, fouling was reduced. The polyamide NF membrane coated with PVA was resistant to the acidic and basic solution.

Autopsy of Nanofiltration membrane of a decentralized demineralization plant

  • El-ghzizel, Soufian;Jalte, Hicham;Zeggar, Hajar;Zait, Mohamed;Belhamidi, Sakina;Tiyal, Fathallah;Hafsi, Mahmoud;Taky, Mohamed;Elmidaoui, Azzedine
    • Membrane and Water Treatment
    • /
    • v.10 no.4
    • /
    • pp.277-286
    • /
    • 2019
  • In 2014, the first demineralization plant, using nanofiltration (NF) membrane coupled with renewable energies was realized at Al Annouar high school of Sidi Taibi, Kenitra, Morocco. This project has revealed difficulties related to the membrane performances loss (pressure increase, flux decline, poor water quality of the produced water and increase of energy consumption), as consequences of membrane fouling. To solve this problem, an autopsy of the membrane was done in order to determine the nature and origin of the fouling. The samples of membrane and fouling were then analyzed by scanning electron microscopy using a scanning electron microscope (SEM) connected with an energy dispersive X-ray (EDX) detection system and X-ray diffractometer (XRD). Moreover, three cleaning solutions (hydrochloric acid, nitric acid and sulfuric acid) were tested and assessed in a single cleaning step to find the suitable one for the fouled membrane to regain its initial permeability and performances. The analysis of the experimental results showed that the fouling layer is mainly composed of calcium carbonate (inorganic fouling). Results showed also that the permeability is improved by the hydrochloric acid cleaning (pH=3) with a cleaning efficiency of 93%. Cleaning efficiency did not exceed 75 % with nitric acid (pH=3) and 40 % with sulfuric acid (pH=3).

Preparation and Characterization of PVA/SA Blend Nanofiltration membranes

  • Llee, Kew-Ho
    • Korean Membrane Journal
    • /
    • v.1 no.1
    • /
    • pp.86-92
    • /
    • 1999
  • The nanofiltration (NF) membranes based on poly(vinyl alcohol) (PVA) and sodium alginate (SA) were prespared. Homogeneous PVA/SA blend membranes were prepared by casting a PVA/SA (95/5 in wi%) mixture solution on an acryl plate followed by drying at a room temperature and by cros-slinking with glutaraldehyde (GA) for 20 minutes PVA/SA blend composite membranes were also prepared by coating a PVA/SA (95/5 in wi%) mixture solution on microporous polysulfone(PSF) supports. The PVA/SA active layer of the composite membrane was crosslinked at room temperature by using an membranes were characterized with a scanning electron microscopy (SEM) a fourier transform infrared spectroscopy (FTIR) and permeation tests. The permeation properties of the composite membrane were as follows: 1.3{{{{ {m }^{2 } }}}}/{{{{ {m }^{2 } }}}}day of flux and >95% of rejection at 200 psi for a 1000 ppm PEG600 solution.

  • PDF

Treatment of a dye solophenyle 4GE by coupling electrocoagulation / nanofiltration

  • Djahida, Zerrouki;Amel, Benhadji;Mourad, Taleb Ahmed;Hayet, Djelal;Rachida, Maachi
    • Membrane and Water Treatment
    • /
    • v.5 no.4
    • /
    • pp.251-263
    • /
    • 2014
  • The study contributes in the treatment of waste generated by the textile complex cotton of Draa Ben Khedda, Algeria. The azo dye "Direct Red Solophenyle 4GE" represents the base particle of the discharges and electrocoagulation with nanofiltration are used as a means of treatment. The solar photovoltaic is suitable for electrochemical process to reduce the energy cost. Several study parameters are considered in this work. The electrocoagulation batch gives the best reduction 37% for a dye concentration of 7.21 mg/L ($[NaCl]_{added}$=1g/L; $j=25.2mA/cm^2$). Coupling methods (electrocoagulation-nonofiltration) gives a complete discoloration rejecting concentration 52.4 mg/L (pHi = 7.6, $[NaCl]_{added}$=3g/L, $j=2.13mA/cm^2$). The result shows the coupling efficiency with a reduced amount of resulting slurry at the end of treatment.

Rejection Behavior of 2-MIB and Geosmin Using Polyethersulfone Nanofiltration Membrane and Surface Hydrophilicity Effect Using $TiO_2$ Particles (2-MIB와 Geosmin의 Polyethersulfone 나노 분리막 배제율 거동 및 $TiO_2$ 적용 표면 친수화 효과 관찰)

  • Nam, Dowoo;Kim, Mooin;Kim, Jeonghwan
    • Membrane Journal
    • /
    • v.22 no.5
    • /
    • pp.326-331
    • /
    • 2012
  • In this study, rejection behavior of 2-MIB (methylisoborneal) and geosmin which are known as taste-and-odor (T & O) causing micropollutants in drinking water source was investigated using hydrophobic polyethersulfone (PES) nanofiltration "loose" membrane (MWCO : 400 Da). It was found that the rejection of the geosmin was higher than that of the 2-MIB in all experimental conditions tested. This study also showed that the rejections of 2-MIB and geosmin were increased by increasing solution pH due to enhancing electrostatic repulsions between micropollutants and membrane surface. The presence of natural organic matter led to increase the rejection of the hydrophobic 2-MIB and geosmin and the effectiveness was more pronounced at higher solution pH. Increasing hydrophilicity of the hydrophobic membrane surface by coating with $TiO_2$ particles resulted in the significant increase in the rejection of 2-MIB and geosmin. In addition to the charge repulsion, this result suggests that hydrophobic-hydrophobic interaction should be one of main rejection mechanisms of T & O compounds by NF membrane.