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Search / Korean Journal of Chemical Engineering
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HWAHAK KONGHAK, Vol.28, No.4, 411-416, 1990
이온교환된 X형 및 Y형 제올라이트의 탈알루미늄에 대한 X선 광전자분광학적 해석
X-ray Photoelectron Spectroscopic Analysis for Dealumination of lon Exchanged Zelite -X and -Y
1N 금속염화물 수용액을 사용한 이온교환반응에서 X형 및 Y형 제올라이트로부터 Al 원자가 빠져나가는 탈알루미늄 현상에 대해 양이온의 영향을 조사하였다. X선 광전자분광법(XPS)과 X선 형광분석법(XRF)을 통해 Na+, Ca2+, Fe2+, Fe3+가 교환된 제올라이트의 탈알루미늄을 연구하였다. 이온교환된 제올라이트의 내부조성과 표면에서의 Al/Si 비를 양이온의 pKh 값과 관련지어 연구하였다. 특히 제올라이트 표면에서의 Al/Si 비를 얻거나 알루미늄원자의 2p궤도 전자결합 에너지를 결정하기 위하여 XPS법이 이용되었다. 실험적인 결과로서 내부보다는 표면의 Al/Si 비가 작았으며 XPS를 통해서 Al2p 전자의 전자결합에너지가 표면의 알루미늄 함량감소에 따라 비례적으로 감소함을 알 수 있었다. 이같은 사실은 표면에서의 Al/Si 비의 감소와 골격내 Al-O 결합의 결합력 약화가 직접적으로 서로 연관되어 있기 때문이다.
The chemical extraction of Al atoms from X and Y zeolites during ion-exchanged procedures using 1N metal chloride solution was studied to investigate the effect of cation on dealumination. Correlated X-ray photoelectron spectroscopy(XPS) and X-ray fluorescence spectroscopy(XRF) studies have been carried out on the dealumination of Na+, Ca2+, Fe2+ -and Fe3+ -exchanged zeolites. The Al/Si ratios of bulk and surface on ion-exchanged zeolite were studied as a function of pKh. Especially, XPS has been used to obtain the Al/Si ratio of zeolite surface and to determine the binding energy(Eb) of Al2p electron. We found that the Al/Si ratio of the surface is less than that of the bulk. The XPS results show that decreasing aluminum content of surface proportionally decrease the binding energy of Al2p elec-tron. It has been also derived that the decrease of surface Al/Si ratio is directly related to the weakening of Al-O bond in framework.
[References]
- Break DW, "Zeolite Molecular Sieves," John Wiley & Sons, New York, 1974
- Rabo JA, "Zeolite Chemistry and Catalysis," ACS Monograph 171, Washington D.C., 1976
- Decanio SJ, Sohn JR, Fritz PO, Lunsford JH, J. Catal., 101, 132, 1986
- Arribas J, Corma A, Fornes V, Melo F, J. Catal., 108, 135, 1987
- Aparicio LM, Dumestic JA, Fang SM, Long MA, Ulla MA, Millman WS, Hall WK, J. Catal., 104, 381, 1987
- Kuhl GH, Zeolites, 5, 4, 1985
- Heo NH, Patalinghug WC, Seff K, J. Phys. Chem., 90, 3931, 1986
- Kim JT, Kim MC, Okamoto Y, Imanaka T, J. Catal., 115, 319, 1989
- Barthomeuf D, Beaumont R, J. Catal., 26, 218, 1972
- Tsutsumi K, Kajiwara H, Takahashi H, Bull. Chem. Soc. Jpn., 47, 801, 1974
- No KT, Chon HZ, Lee TK, John MS, J. Phys. Chem., 85, 2065, 1981
- Barthomeuf D, J. Phys. Chem., 88, 42, 1984
- Sohn JR, Decanio SJ, Lunsford JH, Odonell DJ, Zeolites, 6, 225, 1986
- Szostak R, Thomas TL, J. Catal., 101, 549, 1986
- Melchoir MT, Vaughan DEW, Jacobson AJ, J. Am. Chem. Soc., 104, 4859, 1982
- Fichtner SH, Lohse U, Engelhardt G, Patzelova V, Cryst. Res. Tech., 19, K1, 1984
- Beyerlein RA, McVicker GB, Yacullo LN, Ziemiak JJ, J. Phys. Chem., 92, 1967, 1988
- Finster J, Lorentz P, Chem. Phys. Lett., 50, 223, 1977
- Barr TL, Lishka MA, J. Am. Chem. Soc., 108, 3178, 1986
- Jacobs PA, "In Structure and Reactivity of Modified Zeolites," Elsevier, Amsterdam, 1984
- Contarini S, Kevan L, J. Phys. Chem., 90, 1630, 1986
- Contarini S, Michalik J, Narayana M, Kevan L, J. Phys. Chem., 90, 4586, 1986
- Okamoto Y, Tomioka H, Kaoth Y, Imanaka T, Teranishi S, J. Phys. Chem., 84, 1833, 1980
- Holl Y, Touroude R, Maire G, Muller A, Engelhard PA, Grosmangin J, J. Catal., 104, 202, 1987
- Yong YS, Howe RF, Hughes AE, Jaeger H, Sexton BA, J. Phys. Chem., 91, 6331, 1987
- Barr TL, Chen LM, Mohsenian M, Lishka MA, J. Am. Chem. Soc., 110, 7962, 1988
- Carlson TA, "Photoelectron and Auger Spectroscopy," 2nd ed., Plenum Press, New York, 1978
- Huheey JE, "Inorganic Chemistry," 3rd ed., Happer & Row Co., New York, 1983
- Rees L, J. Chem. Soc.-Faraday Trans., 83, 1531, 1987
- Barrer RH, "Hydrothermal Chemistry of Zeolites," Academic Press, London, 1982
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