Membrane Journal (멤브레인)

The Membrane Society of Korea (한국막학회)
권호 표지
DOI QR코드

DOI QR Code

Studies on the Preparation of Nanofiltration Membrane for Ultra-low Pressure Application through Hydrophilization of Porous PVDF Membrane Using Inorganic Salts

무기염을 이용한 다공성 PVDF 고분자막의 친수화를 통한 초저압용 나노여과막 제조 연구

  • Park, Chan Jong (College of Life Science & Nano Technology, Department of Chemical Engineering, Hannam University) ;
  • Cho, Eun Hye (College of Life Science & Nano Technology, Department of Chemical Engineering, Hannam University) ;
  • Rhim, Ji Won (College of Life Science & Nano Technology, Department of Chemical Engineering, Hannam University) ;
  • Cheong, Seong Ihl (College of Life Science & Nano Technology, Department of Chemical Engineering, Hannam University)
  • 박찬종 (한남대학교 대덕밸리캠퍼스 생명.나노과학대학 화학공학과) ;
  • 조은혜 (한남대학교 대덕밸리캠퍼스 생명.나노과학대학 화학공학과) ;
  • 임지원 (한남대학교 대덕밸리캠퍼스 생명.나노과학대학 화학공학과) ;
  • 정성일 (한남대학교 대덕밸리캠퍼스 생명.나노과학대학 화학공학과)
  • Received : 2014.02.06
  • Accepted : 2014.02.27
  • Published : 2014.02.28
Download PDF
⟨ Previous Next ⟩

Abstract

To prepare the hollow fiber nanofiltration composite membranes, the poly(vinylidene fluoride) (PVDF) membrane was hydrophilized with $K_2Cr_2OH$ and $KMnO_4$ aqueous solutions. And then the composite membrane was synthesized on that membrane surfaces using interfacial polymerization with piperazine (PIP) and trimesoyl chloride (TMC). The resulting membranes were characterized in terms of the rejection and flux for NaCl, $CaSO_4$, $MgCl_2$ 100 ppm solution and 300 ppm of NaCl and $CaSO_4$ mixed solution by varying the coating time, drying time, and the concentration of the coating materials. As a result, the higher rejections were shown for $K_2Cr_2OH$ solutionas a hydrophilization material, and the flux was enhanced while the rejection reduced as the hydrophilization time is longer. Also, the rejection increased and the flux reduced as the concentrations of triethyl amine (TEA) and sodium lauryl sulfate (SLS) were higher. Typically, the rejection 50% and flux 40 LMH for NaCl 100 ppm solution, and the rejection 55% and flux 48 LMH for $CaSO_4$ 100 ppm solution were obtained for the PVDF hollow fiber composite membrane prepared with the conditions of PIP 2 wt% (Triethyl amine (TEA) 7 wt%, SLS 20 wt% mixed solution against PIP concentration) and TMC 0.1 wt%.

초저압용 나노여과 중공사 복합막을 제조하기 위하여 poly(vinylidene fluoride) (PVDF) 소수성 중공사막 표면에 무기염인 $K_2Cr_2OH$와 $KMnO_4$ 수용액으로 친수화 처리를 하였으며, 처리된 막 표면 위에 piperazine (PIP)과 trimesoyl chloride (TMC)로 계면 중합하여 복합막을 제조하였다. NaCl, $CaSO_4$, $MgCl_2$ 100 ppm 용액 및 300 ppm의 NaCl과 $CaSO_4$ 혼합용액을 이용하여 코팅물질의 농도, 코팅시간 및 건조시간에 따른 복합막의 투과특성을 알아보았다. 실험 결과 친수화 물질로는 $K_2Cr_2OH$을 사용하였을 때 더 높은 배제율을 보였으며, 친수화 시간이 길어질수록 투과도는 향상되고 배제율은 감소하는 경향을 나타내었다. 또한 촉매인 triethyl amine (TEA)과 sodium lauryl sulfate (SLS)의 농도가 높을수록 투과도는 감소하고, 염제거율은 증가하였다. 최적 조건으로는 $K_2Cr_2OH$으로 10분 동안 친수화 시킨 PVDF 중공사막 위에 PIP 2 wt% 용액(PIP 함량 대비 Triethyl amine (TEA) 7 wt%, SLS 20 wt% 혼합용액)과 TMC 0.1 wt%를 이용하여 계면중합한 것으로 공급액 NaCl 100 ppm에 대해서는 투과도 40 LMH, 제거율 50%이었고, $CaSO_4$ 100 ppm에 대해서는 투과도 48 LMH, 제거율 55%를 나타내었다.

Keywords

References

  1. Myung Man Kim and Jong Won Park, "A Study on Reverse Osmosis Composite Membrane with polysulfone supporting membrane", Membrane Journal, 4(1), 38 (1994).
  2. R. L. Riley and H. K. Lonsdale, "Preparation of ultrathin reverse osmosis membranes and the attainment of theoretical salt rejection", J. Appl. Polym. Sci., 11, 2143 (1967). https://doi.org/10.1002/app.1967.070111106
  3. Tong C. Hsu and Michael Malone, "Separating Forces in Blade Coating of Viscous and Viscoelastic Fluids", Journal of Non-Newtonian Fluid Mechanics, 18, 273 (1985). https://doi.org/10.1016/0377-0257(85)87003-8
  4. Paul W. Morgan, Condensation polymers: by interfacial and solution methods, Interscience Publishers, New York (1965).
  5. Jong Weon Pak and Hee Jin Kim, "Manufacture of the Thin-Film Composite Membranes for the Teverse Osmosis Process using Interfacial Polymerization Technique", Membrane Journal, 8(1), 29 (1998).
  6. Craig R. Bartels and Kenneth L. Kreuz, "Structureperformance relationships of composite membranes: Porous support densification" J. Membr. Sci., 32, 291 (1987). https://doi.org/10.1016/S0376-7388(00)85013-9
  7. Jong Weon Pak and Bok Byoung Jin, "Reaction Mechanism and Thickness of Thim Film in Interfacial Polymerization", Hwahak konghak, 36, 393 (1998).
  8. J. E. Cadotte, "Interfacially synthesized reverse osmosis membrane", US Pat., 4,277,344 (1981).
  9. Mikhail Kozlov and Mamle Quarmyne, "Adsorption of Poly(vinyl alcohol) onto Hydrophobic Substrates. A General Approach for Hydrophilizing and Chemically Activating Surfaces", Macromolecules, 36, 6054 (2003). https://doi.org/10.1021/ma021681g
  10. Takeshi Serizawa and Satoko Kamimura, "Layerby- Layer Assembly of Poly(vinyl alcohol) and Hydrophobic Polymers Based on Their Physical Adsorption on Surfaces", Langmuir, 18, 8381 (2002). https://doi.org/10.1021/la0204491
  11. Shubhangi G. Gholap and Manohar V. Badiger, "Molecular origins of wettability of hydrophobic poly(vinylidene fluoride) microporous membranes on poly(vinyl alcohol) adsorption: Surface and interface analysis by XPS", J. Phys. Chem. B, 19, 13942 (2005).
  12. hun-Hua Zhanga and Feng-lin Yang, "Preparation and characterization of hydrophilic modification of polypropylene non-woven fabric by dip-coating PVA (polyvinyl alcohol)", Sep. Purif. Tech., 61, 276 (2008). https://doi.org/10.1016/j.seppur.2007.10.019
  13. Yun Feng Yang and Ling Shu Wan, "Surface hydrophilization of microporous polypropylene membrane by the interfacial crosslinking of polyethylenimine", J. Membr. Sci., 337, 70 (2009). https://doi.org/10.1016/j.memsci.2009.03.023
  14. Yong Jin Choi and Sung Won Lee, "Hydrophilic Modification of Porous Polyvinylidene Fluoride Membrane by Pre-irradiating Electron Beam", Membrane Journal, 21(2), 118, (2011).