Membrane Journal (멤브레인)

The Membrane Society of Korea (한국막학회)
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Synthesis and Characteristics of Partially Fluorinated Poly(vinylidene fluroide)(PVDF) Cation Exchange Membrane via Direct Sulfonation

직접술폰화반응에 의한 부분불소화 Poly(vinylidene fluroide)(PVDF) 양이온교환막의 합성 및 특성

  • Kang, Ki Won (Department of Applied Chemistry and Biological Engineering, Chungnam National University) ;
  • Hwang, Taek Sung (Department of Chemical Engineering, College of Enginerring, Chungnam National University)
  • 강기원 (충남대학교 바이오응용화학과) ;
  • 황택성 (충남대학교 화학공학과)
  • Received : 2015.09.25
  • Accepted : 2015.10.22
  • Published : 2015.10.31
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Abstract

In this study, partially fluorinated cation exchange membranes were prepared by direct sulfonation of Poly(VDF-co-hexafluoropropylene) copolymers (PVDF-co-HFP) followed by a casting method for application in the Membrane capacitive deionization (MCDI). The structure of sulfonated PVDF-co-HFP (SPVDF) was confirmed by Fourier-transform infrared (FT-IR) and $^1H$ Nuclear magnetic resonance ($^1H$ NMR) analysis. For quantitative analysis of the chemical composition, the X-ray Photoelectron Spectroscopy (XPS) was used. The membrane properties such as water uptake, ion exchange capacity and electrical resistance were measured. It was suggested that the optimum direct sulfonation condition of PVDF-co-HFP ion exchange membranes was $60^{\circ}C$ and 7 hours for temperature and duration of sulfonation, respectively. The water uptake of the SPVDF ion exchange membrane was 21.5%. The ion exchange capacity and electrical resistance were 0.89 meq/g and $3.70{\Omega}{\cdot}cm^2$, respectively. It was investigated that if it is feasible to apply these membranes in MCDI at various cell potentials (0.9~1.5 V) and initial flow rates (10~40 mL/min). In the MCDI process, the maximum salt removal rate was 62.5% in repeated absorption-desorption cycles.

본 연구에서는 막 축전식 탈이온 공정에 적용하기 위해 온도와 시간을 달리하여 술폰화 Poly(VDF-co-hexafluoropropylene) copolymers (PVDF-co-HFP)을 합성 후 캐스팅법에 의해 양이온교환막이 제조되었다. 술폰화 PVDF (SPVDF)는 Fourier-transform infrared (FT-IR), $^1H$ Nuclear magnetic resonance ($^1H$ NMR)를 통해 구조확인을 하였고, X-ray Photoelectron Spectroscopy (XPS)를 통해 화학조성에 대한 정량적 분석을 하였다. 막 성능은 함수율 및 이온교환용량과 전기저항을 측정하였고. $60^{\circ}C$에서 7시간 술폰화한 SPVDF 멤브레인이 이온교환용량 0.89 meq/g, 함수율 21.5%, 전기저항 $3.70{\Omega}{\cdot}cm^2$로 가장 우수하였다. 수중 이온제거 특성을 막 축전식 탈이온 방법(MCDI)으로 전압(0.9~1.5 V), 유속(10~40 mL/min)을 변수로 SPVDF의 탈염 특성을 확인하여 MCDI 공정에 적용가능 여부를 평가하였다. MCDI 충방전 시험 결과 최대 탈염제거율은 62.5%이었다.

Keywords

References

  1. V. K. Gupta, I. Ali, T. A. Saleh, A. Nayak, and S. Agarwal, "Chemical treatment technologies for waste-water recycling-an overview", RSC Advances, 2, 6380 (2012). https://doi.org/10.1039/c2ra20340e
  2. P. Biesheuvel and A. Van der Wal, "Membrane capacitive deionization", J. Membr. Sci., 346 256 (2010). https://doi.org/10.1016/j.memsci.2009.09.043
  3. F. A. AlMarzooqi, A. A. Al Ghaferi, I. Saadat, and N. Hilal, "Application of capacitive deionisa tion in water desalination: A review", Desalination, 342, 3 (2014). https://doi.org/10.1016/j.desal.2014.02.031
  4. S. J. Seo, J. H. Lee, J. K. Kim, G. Y. Park, D. Nojima, H. Lee, and S. H. Moon, "Investigation on removal of hardness ions by capacitive deionization(CDI) for water softening applications", Water Res., 44, 2267 (2010). https://doi.org/10.1016/j.watres.2009.10.020
  5. S. H. Moon and S. H. yun, "Process integration of electrodialysis for a cleaner environment", Current opinion in chemical engineering, 4, 25 (2014). https://doi.org/10.1016/j.coche.2014.01.001
  6. J. S. Kim and J. H. Choi, "Fabrication and characterization of a carbon electrode coated with cation- exchange polymer for the membrane capacitive deionization applications", J. Membr. Sci., 355, 85 (2010). https://doi.org/10.1016/j.memsci.2010.03.010
  7. H. Li, Y. Gao, L. Pan, Y. Zhang, Y. Chen, and Z. Sun, "Electrosorptive desalination by carbon nanotubes and nanofibres electrodes and ion-exchange membranes", Water Res., 42, 4923 (2008). https://doi.org/10.1016/j.watres.2008.09.026
  8. Y. J. Kim and J. H. Choi, "Enhanced desalination efficiency in capacitive deionization with an ion-selective membrane", Sep. Purif. Tech., 71, 70 (2010). https://doi.org/10.1016/j.seppur.2009.10.026
  9. F. Liu, N. A. Hashim, Y. Liu, M. R. Moghareh Abed, and K Li, "Progress in the production and modification of PVDF membranes", J. Membr. Sci., 375, 1 (2011). https://doi.org/10.1016/j.memsci.2011.03.014
  10. Z. Cui, E. Drioli, and Y. M. Lee, "Recent progress in fluoropolymers for membranes", Prog. Polym. Sci., 39, 164 (2014). https://doi.org/10.1016/j.progpolymsci.2013.07.008
  11. G. Kang and Y. Cao, "Application and modification of poly (vinylidene fluoride)(PVDF) membranes- A review", J. Membr. Sci., 463, 145 (2014). https://doi.org/10.1016/j.memsci.2014.03.055
  12. K. Dutta, S. Das, P. Kumar, and P. P. Kundu, "Polymer electrolyte membrane with high selectivity ratio for direct methanol fuel cells: A preliminary study based on blends of partially sulfonated polymers polyaniline and PVdF-co-HFP", Applied Energy, 118, 183 (2014). https://doi.org/10.1016/j.apenergy.2013.12.029
  13. K. Dutta, S. Das, and P. P. Kundu, "Low methanol permeable and highly selective membranes composed of pure and/or partially sulfonated PVdF-co-HFP and polyaniline", J. Membr. Sci., 468, 42 (2014). https://doi.org/10.1016/j.memsci.2014.05.049
  14. S. Das, P. Kumar, K. Dutta, and P. P. Kundu, "Partial sulfonation of PVdF-co-HFP: a preliminary study and characterization for application in direct methanol fuel cell", Applied Energy, 113, 169 (2014). https://doi.org/10.1016/j.apenergy.2013.07.030
  15. H. Farrokhzad, T. Kikhavani, F. Monnaie, S. Ashrafizadeh, G. Koeckelberghs, T. Van Gerven, and B. Van der Bruggen, "Novel composite cation exchange films based on sulfonated PVDF for electromembrane separations", J. Membr. Sci., 167, 4 (2015).