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졸-겔법에 의한 γ-Al2O3 입자 제조시 수반된 해교반응에 관한 연구
A Study on the Peptization Reaction Accompanied with γ-Al2O 3 Particles Preparation by Sol-Gel Method
HWAHAK KONGHAK, October 1998, 36(5), 695-700(6), NONE
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Abstract
앞에서 보고찬 논문[l]에서 졸 제조공정단계 가운데 숙성이 γ-AlO(OH)입자는 물론 열처리 후의 γ-Al2O3입자의 미세구조 특성에 큰 영향을 미침을 밝혔다. 본 연구는 졸-겔법에 의한 γ-알루미나 입자 제조시 졸 제조 공정 가운데 숙성에 이어 연속공정인 해교반응이 γ-Al2O3 입자 특성에 미치는 영향을 고찰하였다. 연구결과, 해교반응에 따른γ-AlO(OH) 및 γ-Al2O3 입자의 결정구조 및 미세구조 특성은 변화하지 않았으며, 해교반응 초기에 평균 기공경의 일부만 감소하였다. 이는 응집된 γ-AlO(OH) 입자 표면에 흡착된 H2 O 분자가 가해진 산전해질의 H3O+ 이온에 의해 치환되어 입자간 전하반발 효과가 발생되어 응집 입자간에 형성되었던 거대기공이 사라졌기 때문이다. 여기서 해교반응은 수소결합과 oration 결합에의해 결합 응집된 입자들이 산전해질의 H3O+ 이온에의해 끊어져 나타난 현상으로 보인다. γ-Al 2O3 입자 제조를 위한 γ-AlO(OH) 졸 제조공정의 영향을 종합해보면해교반응은전해질첨가로미세하게분산된졸을만들기 위한 공정이고, Y-AlO(OH) 및 γ-Al2O3 입자의 미세구조 특성은 주로 숙성에 의해 조절 가능함을 알았다
In the previous study(1), we showed that the microstructure of γ-AlO(OH) and γ-Al 2O3 particles was affected by aging stage in the γ-AlO (OH) sol preparation process. We investigated the effects of peptization as a continuous process after aging in γ-AlO(OH) sol preparation process on characterization of γ-Al 2O3 particles in this study. From the results, we found that there was no crystallinity and microstructure changes of γ-Al 2O3 particles as well as γ-AlO(OH) particles according to peptization. But there was a decrease of average pore diameter in γ-AlO(OH) particles at the beginning of the peptization. It shows that the adsorbed H2O molecules on agglomerated γ-AlO(OH) particles were replaced by H3 O+ of added peptization agent and then γ-AlO(OH) particles were repulsed against each other. As the result, the macropores within γ-AlO(OH) particles disappeared. Here, the peptization phenomenon occurred since agglomerated particles binded hydrogen bonds and olation bonds have been broken their bonds by the added H3O+, there was happened to be peptization phenomenon. In summary, we concluded that microstructure of γ-Al2O3, particles was controlled by aging stage in sol preparation process and peptization was the process of finely suspended γγ-AlO(OH) sol preparation.
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References
Yoo SJ, Lee JW, Hwang UY, Yoon HS, Park HS, HWAHAK KONGHAK, 35(6), 832 (1997)
Khan KC, Brownstein AK, Ceram. Bull., 70, 703 (1991)
Ma MK, Kwon HS, Mah SK, Chung IJ, HWAHAK KONGHAK, 29(5), 557 (1991)
Yoldas BE, Am. Ceram. Soc. Bull., 54(3), 289 (1975)
Wells AF, "Structural Inorganic Chemistry," 5th Ed., Oxford (1984)
Yoldas BE, J. Mater. Sci., 10, 1856 (1975)
Livage J, Henry M, Sanchez C, Pro. Solid St. Chem., 118, 259 (1988)
Komarneni S, Roy R, Fyfe CA, Kennedy GJ, J. Am. Ceram. Soc., 68(9), C243 (1985)
Anderson MA, Gieselmann MJ, Qunyin X, J. Membr. Sci., 39, 243 (1988)
Khan KC, Brownstein AK, Ceram. Bull., 70, 703 (1991)
Ma MK, Kwon HS, Mah SK, Chung IJ, HWAHAK KONGHAK, 29(5), 557 (1991)
Yoldas BE, Am. Ceram. Soc. Bull., 54(3), 289 (1975)
Wells AF, "Structural Inorganic Chemistry," 5th Ed., Oxford (1984)
Yoldas BE, J. Mater. Sci., 10, 1856 (1975)
Livage J, Henry M, Sanchez C, Pro. Solid St. Chem., 118, 259 (1988)
Komarneni S, Roy R, Fyfe CA, Kennedy GJ, J. Am. Ceram. Soc., 68(9), C243 (1985)
Anderson MA, Gieselmann MJ, Qunyin X, J. Membr. Sci., 39, 243 (1988)
