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이홍림,김세기,이온영,정원도,김창은,이희수 연세대학교 산업기술연구소 1989 논문집 Vol.21 No.1
The gel powder of cordierite composition was prepared from Mg(NO₃)₂6H₂O, Al[ OCHCH₂(CH₃)₂] ₃ and Si(OC ₂??)₄ as sources of Mg, Al and Si-components, using isopropyl alcohol al a solvent and NH₄OH as a catalyst. Due to the difference of hydrolysis rates between Si(OC₂??)₄ and Al[ OCHCH₂(CH₃)₂]₃, the small amount of spinel was formed besides the main phase, cordierite, after clacining. At 900 ℃, μ-cordierite, the low temperature metastable form, was appeared but transformed to α-phase, the high stable form, when calcined at 1100 ℃ for 2h. The specific surface area and mean particle size of powder calcined at 600 ℃ for 2h were 62m²/g and 0.552μm, respectively. However, when acetylacetone was added to Al [OCHCH₂(CH₃)₂]₃ as a stabilizer, the transformation temperature was lowered about 80 ℃. The powder calcined at 600℃ was more porous than the former, resulting the specific surface area and mean particle size of the power to be 236 m²/g and 0.724μ m, respectively.