Al2(SO4)3 용액의 가수분해에 의해 얻어진 Aluminum Hydroxides Gel의 pH가 판상 α-Al2O3의 결정성장에미치는영향 = Effect of pH of Aluminum Hydroxides Gel Obtained by Hydrolysis of Al2(SO4)3 Solution on Crystal Growth ofα-Al2O3 Platelets

다국어 초록 (Multilingual Abstract)

To precipitate the complex gels of the pH 6, 7, 8, 9 included in a flux and an aluminum hydroxides gel, an aqueous solution of a
mixture of Na2CO3 and Na2PO4
·12H2O was added with stirring in an aqueous solution of a mixture of Al2(SO4)3
·18H2O, Na2SO4
and K2SO4, and then the complex gels were aged in 20 h at 90
o
C. As the hydrolysis pH changed, it had an effect on the physical
properties such as the crystal structure, crystal morphology and a phase transition temperature of the AlO(OH) gel, and also on the
crystal structure, crystal morphology, particle size and particle size distribution of the α-Al2O3 platelets prepared by molten-salt
precipitation. Also, in this study, the complex gels were crystallized at 1,200
o
C and thereafter dried at 110
o
C, and then it was
investigated to effect of the hydrolysis pH on the crystal structure, morphology and particle size distribution of the α-Al2O3 platelets
crystals using XRD, DTA, SEM and particle size analyzer.

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