Articles & Issues
- Conflict of Interest
- In relation to this article, we declare that there is no conflict of interest.
-
This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/bync/3.0) which permits
unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Copyright © KIChE. All rights reserved.
All issues
크롬 및 구리가 담지된 La2O3/Al2O3 계 복합산화물 촉매의 구조 및 열안정성
Structure and Thermal Properties of Cr and Cu Added La2O3/Al2O3 System
HWAHAK KONGHAK, December 1994, 32(6), 859-865(7), NONE
Download PDF
Abstract
크롬, 구리가 담지된 La2O3/Al2O3계 복합산화물 촉매의 구조 및 열적 특성이 XRD, 질소 흡착, ESCA, TEM 및 DTA둥에 의해 조사되었다. 크롬이 담지된 경우에 La2O3/Al2O3계 복합산화물은 소성 과정에서 La-β-Al2O3로의 상전이가 억제되었으나, 구리가 담지된 경우에는 상전이가 촉진되었다. (Cr2O3)(La2O3)(Al2O3)19 복합산화물의 경우에 1,200℃에서 2시간 소성시킨 후에 비표면적인 40m²/g정도였으나, (CuO)(La2O3)(Al2O3)19 복합산화물은 같은 조건에서 10m2/g 정도의 낮은 비표면적 값을 나타내었다. 1,000℃에서 La2O3/Al2O3 계 복합산화물의 sintering은 표면 확산 기구를 통하여 진행되며, 크롬이 담지된 경우에는 그 영향을 받지 않으나 구리가 담지되면 sintering은 유동 기구를 통하여 진행되었다. 1,200℃이상에서 La2O3/Al2O3계 복합산화물의 상전이에 따른 활성화 에너지는 크롬이나 구리의 담지에 관계없이 약 600 kJ/mol 정도로 거의 비슷하였다.
The structure and thermal properties of Cr and Cu added La2O3/Al2O3 System were investigated using XRD, BET, ESCA, TEM and DTA. During calcination the addition of chromium retarded the phase transition of La-β-Al2O3 and improved the thermal stability of La2O3/Al2O3 System at highly temperature. However the addition of copper on La2O3/Al2O3 System accelerated the phase transition of support. The surface area after being calcined at 1,200℃ for 2 hours was 40㎡/g for (Cr2O3)(La2O3)(Al2O3)19 oxide and 10㎡/g for (CuO)(La2O3)(Al2O3)19 oxide. The sintering of La2O3/Al2O3 System at 1,000℃ proceeded via surface diffusion and was not influenced by the Cr addition. The sintering of Cu added La2O3/Al2O3 System proceeded via viscous flow. The activation energy of the phase transition above 1,200℃ had a constant value about 600 kJ/mol, regardless of the Cr and Cu addition.
References
Dwyer FG, Catal. Rev.-Sci. Eng., 6, 261 (1972)
Shelef M, Catal. Rev.-Sci. Eng., 11, 1 (1975)
Trimm DL, Appl. Catal. A: Gen., 7, 249 (1983)
Prasad R, Kennedy LA, Ruckkenstein R, Catal. Rev.-Sci. Eng., 26, 1 (1984)
Matsuta S, Kato A, Mizumoto M, Yamashita H, "Proceedings, 8th International Congress on Catalysis," Berlin, Vol. 4, p. 879, Dechema Frank-furt (1984)
Machida M, Eguchi K, Arai H, J. Catal., 103, 385 (1987)
Kato A, Yamashita H, Kawagoshi H, Matsuta S, J. Am. Ceram. Soc., 70, C157 (1987)
Shelef M, Otto K, gandhi H, J. Catal., 12, 361 (1968)
Clark A, Catal. Rev.-Sci. Eng., 3, 145 (1969)
McDaniel MD, Adv. Catal., 33, 47 (1985)
Kissinger HE, Anal. Chem., 29, 1072 (1957)
Ropp RC, Carroll B, J. Am. Ceram. Soc., 63, 416 (1980)
Frische ET, Tensmeyer LG, J. Am. Ceram. Soc., 50, 167 (1967)
Lowell S, Shields JE, "Powder Surface Area and Porosity," Champman and Hall, New York, p. 62 (1984)
Suh JK, Ha BH, Koh JC, Lee JM, HWAHAK KONGHAK, 31(6), 667 (1993)
German RM, Munir ZA, J. Am. Ceram. Soc., 59, 379 (1976)
Schaper H, Doesburg EBM, vanReijen LL, Appl. Catal., 7, 211 (1983)
Raman SV, Doremus RH, German RM, "Sintering and Heterogeneous Catalysis," Ed. Plenum Press, New York, p. 253 (1984)
Ozawa M, Kimura M, J. Jpn. Soc. Powder Powder Metallurgy, 37, 466 (1990)
Shelef M, Catal. Rev.-Sci. Eng., 11, 1 (1975)
Trimm DL, Appl. Catal. A: Gen., 7, 249 (1983)
Prasad R, Kennedy LA, Ruckkenstein R, Catal. Rev.-Sci. Eng., 26, 1 (1984)
Matsuta S, Kato A, Mizumoto M, Yamashita H, "Proceedings, 8th International Congress on Catalysis," Berlin, Vol. 4, p. 879, Dechema Frank-furt (1984)
Machida M, Eguchi K, Arai H, J. Catal., 103, 385 (1987)
Kato A, Yamashita H, Kawagoshi H, Matsuta S, J. Am. Ceram. Soc., 70, C157 (1987)
Shelef M, Otto K, gandhi H, J. Catal., 12, 361 (1968)
Clark A, Catal. Rev.-Sci. Eng., 3, 145 (1969)
McDaniel MD, Adv. Catal., 33, 47 (1985)
Kissinger HE, Anal. Chem., 29, 1072 (1957)
Ropp RC, Carroll B, J. Am. Ceram. Soc., 63, 416 (1980)
Frische ET, Tensmeyer LG, J. Am. Ceram. Soc., 50, 167 (1967)
Lowell S, Shields JE, "Powder Surface Area and Porosity," Champman and Hall, New York, p. 62 (1984)
Suh JK, Ha BH, Koh JC, Lee JM, HWAHAK KONGHAK, 31(6), 667 (1993)
German RM, Munir ZA, J. Am. Ceram. Soc., 59, 379 (1976)
Schaper H, Doesburg EBM, vanReijen LL, Appl. Catal., 7, 211 (1983)
Raman SV, Doremus RH, German RM, "Sintering and Heterogeneous Catalysis," Ed. Plenum Press, New York, p. 253 (1984)
Ozawa M, Kimura M, J. Jpn. Soc. Powder Powder Metallurgy, 37, 466 (1990)
