Applied Chemistry for Engineering, Vol.24, No.3, 247-252, June, 2013
Sulfonated Poly(Ether Ether Ketone)을 코팅한 이온선택성 복합탄소전극의 제조 및 전기화학적 특성 분석
Fabrication and Electrochemical Characterization of Ion-selective Composite Carbon Electrode Coated with Sulfonated Poly(Ether Ether Ketone)
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초록
반응시간을 변화시키면서 poly(ether ether ketone) (PEEK)을 황산과 반응시켜 술폰화도가 다른 sulfonated PEEK (SPEEK)를 합성하였다. 제조한 SPEEK를 탄소전극 표면에 코팅하여 이온선택성 복합탄소전극(ion-selective composite carbon electrode, ISCCE)을 제조하였다. 임피던스 분석을 통해 제조한 ISCCE의 비정전용량과 전기저항을 측정하였다. 술폰화 반응 시간에 따라 SPEEK의 이온교환용량은 1.60∼2.57 meq/g으로 측정되었다. 그러나 이온교환용량이 2.5 meq/g 이상에서는 SPEEK가 일부 물에 용해되어 ISCCE 제조에 부적합하였다. ISCCE에 대한 정전용량을 측정한 결과 코팅된 SPEEK의 이온교환용량이 증가함에 따라 정전용량도 증가하였으며 코팅하지 않은 탄소전극에 비해 최대 20%까지 향상되었다. 또한 코팅층의 전기저항은 SPEEK의 이온교환용량이 증가함에 따라 크게 감소하였다. 따라서 SPEEK가 코팅된 ISCCE를 이용하여 기존 축전식 탈염(capacitive deionization, CDI) 공정의 탈염효율을 크게 향상시킬 수 있을 것으로 기대된다.
Sulfonated poly(ether ether ketone) (SPEEK) with a certain degree of sulfonation were synthesized by reacting PEEK and sulfuric acid at different reaction time. Then ion-selective composite carbon electrodes (ISCCE) were fabricated by coating the prepared SPEEK on the surface of carbon electrodes. The specific capacitance and resistance of the ISCCE were analyzed by electrical impedance spectroscopy. The ion exchange capacities (IEC) of the SPEEKs were measured in the range of 1.60 ∼2.57 meq/g depending on the sulfonation time. The SPEEK more than 2.5 meq/g of IEC was considered unsuitable for fabricating the ISCCE because it was dissolved in water. The specific capacitance of the prepared ISCCE increased with increasing the IEC of coated SPEEKs and the capacitance was improved up to about 20% compared to that of uncoated carbon electrode. In addition, the electrical resistance of coating layer decreased significantly with increasing the IEC of coated SPEEKs. It is expected that the desalination efficiency of conventional capacitive deionization process can be improved by using the prepared ISCCE coated with SPEEK.
Keywords:capacitive deionization;sulfonated poly(ether ether ketone);ion exchange capacity;composite carbon electrode;specific capacitance
- Oren Y, Desalination, 228(1-3), 10 (2008)
- Anderson MA, Cudero AL, Palma J, Electrochim. Acta, 55(12), 3845 (2010)
- Ryoo MW, Seo G, Water. Res., 37, 1527 (2003)
- Biesheuvel PM, J. Colloid Interface Sci., 332(1), 258 (2009)
- Li H, Zou L, Pan L, Sun Z, Environ. Sci. Technol., 44, 8692 (2010)
- Kim YJ, Choi JH, Sep. Purif. Technol., 71(1), 70 (2010)
- Li H, Gao Y, Pan L, Zhang Y, Chen Y, Sun Z, Water Res., 42, 4923 (2008)
- Lee JH, Bae WS, Choi JH, Desalination, 258(1-3), 159 (2010)
- Biesheuvel PM, van der Wal A, J. Membr. Sci., 346(2), 256 (2010)
- Andelman MD, CA Patent 2444390 (2002)
- Lee JB, Park KK, Eum HM, Lee CW, Desalination, 196(1-3), 125 (2006)
- Kim YJ, Choi JH, Water Res., 44, 990 (2010)
- Muthu LRTS, Choudhary V, Varma IK, J. Mater. Sci., 40(3), 629 (2005)
- Kreuer KD, J. Membr. Sci., 185(1), 29 (2001)
- Shibuya N, Porter RS, Macromolecules., 25, 6495 (1992)
- Huang RYM, Shao PH, Burns CM, Feng X, J. Appl. Polym. Sci., 82(11), 2651 (2001)
- Strathmann H, Ion-Exchange Membrane Separation Processes, Elsevier, Amsterdam (2004)
- Probstle H, Wiener M, Fricke J, J. Porous Mater., 10, 213 (2003)
- Park BH, Kim YJ, Park JS, Choi J, J. Ind. Eng. Chem., 17(4), 717 (2011)
- Johnson BC, Yilgor I, Tran C, Iqbal M, Wightman JP, Lloyd DR, Mcgarth JE, J. Polym. Sci., 22, 721 (1984)
- Bard AJ, Faulkner LR, Electrochemical Methods: Fundamentals and Application, 2nd Ed., John Wiley & Sons, Inc. (2001)
- Conway BE, Electrochemical Supercapacitors: Scientific Fundamentals and Technological Applications, Kluwer Academic/Plenum Publishers, New York (1999)
- Park BH, Choi JH, Electrochim. Acta, 55(8), 2888 (2010)
- Kim YJ, Choi JH, Appl. Chem. Eng., 21(1), 87 (2010)
- Gabelich CJ, Tran TD, I. H. “MEL” Suffet, Environ. Sci.Technol., 36, 3010 (2002)