Membrane and Water Treatment

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Morphology control in PVDF membranes using PEG/PVP additives and mixed solvents

  • Received : 2018.09.07
  • Accepted : 2020.05.21
  • Published : 2020.07.25
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Abstract

The effects of the mixed two solvents, Dimethylacetamide (DMAc) and Dimethylformamide (DMF), and Polyethylene glycol (PEG) and Polyvinylpyrrolidone (PVP) as additives on performance of Polyvinylidene fluoride (PVDF) membranes were studied. Initially, PEG200 was used as a primary additive at fixed percentage of 5% wt. PVP was then blended with PEG200 in different concentrations. PVDF and DMAc were used as polymer and solvent in the casting solutions, respectively. To control the diffusion rate of PVP in the presence of PEG200 and PVP blend, mixtures of DMAc and DMF were used as the mixed solvent in the casting solutions. Asymmetric PVDF membranes were prepared via phase inversion process in a water bath and the effects of two additives and two solvents on the membrane morphology, pure water flux (PWF), hydrophilicity and rejection (R) were investigated. Attenuated Total Reflection Fourier Transform Infrared Spectra (ATR-FTIR) analysis was used to show the residual PVP on the surface of the membranes. Atomic Force Microscopy (AFM) was utilized to determine roughness of membrane surface. The use of mixed solvents in the casting solution resulted in reduction of PVP diffusion rate and increment of PEG diffusion rate. Eventually, PWF and R values reduced, while porosity and hydrophilicity increased.

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References

  1. Bottino, A, Capannelli G., Munari, S. and Torturro, A. (1988), "High performance ultrafiltration membranes cast from PVDF/LiCI doped solutions", Science, 68, 167-177. https://doi.org/10.1126/science.68.1756.167
  2. Chakrabarty, B., Ghoshal, A.K. and Purkait, M.K. (2008), "Preparation, characterization and performance studies of polysulfone membranes using pvp as an additive", J. Membr. Sci., 315(1-2), 36-47. https://doi.org/10.1016/j.memsci.2008.02.027
  3. Fontananova, E., Jansen, J.C., Cristiano, A., Curcio, E. and Drioli, E. (2006). "Effect of Additives in the Casting Solution on the Formation of PVDF Membranes", 192(August 2005), 190-197. https://doi.org/10.1016/j.desal.2005.09.021
  4. Gebru, K.A. and Das, C. (2017), "Effects of Solubility parameter differences among PEG, PVP and CA on the preparation of ultrafiltration membranes: impacts of solvents and additives on morphology, permeability and fouling performances", Chinese J. Chem. Eng., 25(7), 911-923. http://dx.doi.org/10.1016/j.cjche.2016.11.017.
  5. Yoo, S.H., Kim, J.H., Jho, J.Y., Won, J. and Kang, Y.S (2004) "Influence of the Addition of PVP on the morphology of asymmetric polyimide phase inversion membranes: Effect of PVP molecular weight", 236, 203-207. https://doi.org/10.1016/j.memsci.2004.02.017
  6. Ma, Y.X., Shi, F.M. Wu, M.N. and Ma, J. (2011), "Effect of additives in the casting solutions on the morphology and performance of PVDF membranes", Adv. Mater. Res., 391-392. 1412-1416. https://doi.org/10.4028/www.scientific.net/AMR.391-392.1412
  7. Madaeni, S.S., and Taheri, A.H. (2011), "Effect of Casting Solution on Morphology and Performance of PVDF Microfiltration Membranes", Chem. Eng. Technol., 34(8), 1328- 1334. https://doi.org/10.1002/ceat.201000177
  8. Mohsenpour, S., Safekordi, A., Tavakolmoghadam, M., Rekabdar, F. and Hemmati, M (2016), "Comparison of the Membrane Morphology Based on the Phase Diagram Using PVP as an Organic Additive and TiO2as an Inorganic Additive", Polymer (United Kingdom) 97, 559-568. http://dx.doi.org/10.1016/j.polymer.2016.05.069.
  9. Ngang, H.P., Ahmad, A.L., Low, S.C. and Ooi, B.S. (2014), "The Influence of PEG Additive on the Morphology of PVDF Ultrafiltration Membranes and Its Antifouling Properties towards Proteins Separation", J. Teknologi, 70(2), 23-27.
  10. Shockravi, A., Vatanpour, V., Najjar, Z., Bahadori, S. and Javadi, A. (2017), "A new high performance polyamide as an effective additive for modification of antifouling properties and morphology of asymmetric pes blend ultrafiltration membranes", Microporous Mesoporous Mater., 246, 24-36. http://dx.doi.org/10.1016/j.micromeso.2017.03.013.
  11. Simone, S., Figoli, A., Criscuoli, A., Carnevale, M.C., Rosselli, A. and Drioli, E (2010), "Preparation of Hollow Fibre Membranes from PVDF / PVP Blends and Their Application in VMD", J. Membr. Sci., 364(1-2), 219-232. http://dx.doi.org/10.1016/j.memsci.2010.08.013.
  12. Tavakolmoghadam, M., Mohammadi, T. and Hemmati, T. (2016), "Preparation and Characterization of PVDF / $TiO_2$ Composite Ultrafiltration Membranes Using Mixed Solvents", 5, 377-401. https://doi.org/10.12989/mwt.2016.7.5.377
  13. Ulbricht, M. (2006), "Advanced functional polymer membranes", Polymer, 47(7), 2217-2262. https://doi.org/10.1016/j.polymer.2006.01.084
  14. Vilakati, G.D., Hoek, E.M.V. and Mamba, B.B. (2014), "Probing the mechanical and thermal properties of polysulfone membranes modified with synthetic and natural polymer additives", Polymer Testing, 34(2014), 202-210. https://doi.org/10.1016/j.polymertesting.2014.01.014
  15. Wang, Q., Wang, Z. and Wu, Z. (2012), "Effects of Solvent compositions on physicochemical properties and anti-fouling ability of PVDF microfiltration membranes for wastewater treatment", Desalination, 297, 79-86. http://dx.doi.org/10.1016/j.desal.2012.04.020.
  16. van de Witte, P., Dijkstra, P.J., van den Berg, J.W.A. and Feijen, J. (1996), "Phase separation processes in polymer solutions in relation to membrane formation", J. Membr. Sci., 117(1-2), 1-31. http://linkinghub.elsevier.com/retrieve/pii/0376738896000889. https://doi.org/10.1016/0376-7388(96)00088-9
  17. Yeow, M.L., Liu, Y.T. and Li, K. (2003), "Isothermal phase diagrams and phase-inversion behavior of poly (Vinylidene Fluoride)/ solvents / additives / water systems", J. Appl. Polym. Sci., 90, 2150-2155. https://doi.org/10.1002/app.12846