Journal of the Korean Industrial and Engineering Chemistry, Vol.2, No.2, 119-126, June, 1991
수열균일 침전반응에 의한 Boehmite 합성
Synthesis of Boehmite by Hydrothermal Homogeneous Precipitation Reaction
암모늄명반과 요소를 수열균일 침전법으로 반응시켜 베마이트의 합성을 연구한 것으로, 암모늄명반과 요소와의 몰비를 1 : 2 - 1 : 5, 반응온도를 100-250℃, 반응시간을 30분-20시간으로 변경시키면서 반응시켰다. 반응생성 침전물은 X-선 회절분석, 주사형현미경관찰, 화학분석 등의 방법으로 검토하였다. 암모늄명반과 요소와의 몰비가 1 : 4에서 구상의 단분산 무정형 수화황상알루미늄과 베마이트가 생성되었고, 200℃ 이상에서는 베마이트만이 생성되었다. 반응생성 침전물들은 치밀하고 침강성과 여과성이 좋았고 침전물의 입자는 평균 2-4㎛ 크기였다.
This investigation was undertaken to study the synthesis of Boehmite by the hydrothermal homogeneous precipitation reaction of alum with urea. The reactions were carried out at a temperature of 100 to 250 ℃, 1 : 2 to 1 : 5 in a mole ratio of alum to urea and a reaction time of 0.5 to 20 hrs. The reaction precipitates were examined by X-ray diffraction analysis, scanning electron microscope, and chemical analysis. Under the condition of mole ratio 1 : 4 of alum to urea, the spherical and monodispersed amorphous aluminum sulfate hydrate was formed at 100 ℃, the mixture of spherical amorphous aluminum sulfate hydrate and Boehmite was formed at 150 ℃, Boehmite was formed at above 200 ℃, respectively. The reaction precipitates were dense, superior precipitable and filterable particle of average 2-4 ㎛.
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