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›› 2006, Vol. 6 ›› Issue (4): 580-584.

• 过程与工艺 • 上一篇    下一篇

薄水铝石粒度对煅烧形成a-Al2O3粉体的影响

黎少华,袁方利,胡鹏,柯家骏   

  1. 中国科学院过程工程研究所
  • 出版日期:2006-08-20 发布日期:2006-08-20

Influence of Boehmite Particle Size on the Formation of a-Alumina Powder by Calcination

LI Shao-hua,YUAN Fang-li,HU Peng,KE Jia-jun   

  1. Institute of Process Engineering, Chinese Academy of Sciences
  • Online:2006-08-20 Published:2006-08-20

摘要: 研究了薄水铝石粒度对其煅烧形成a-Al2O3粉体的影响. 先用水热法制备出均匀分散的纳米、亚微米及几个微米的薄水铝石前驱体,用X射线衍射仪和电子显微镜分析了薄水铝石在不同温度煅烧所得产物的相结构及形貌. 结果表明,粒度30~100 nm的薄水铝石在1200℃煅烧1 h转变为a-Al2O3,为蠕虫状的烧结颗粒;粒度0.4~0.6 mm的薄水铝石在1250℃煅烧1 h可转变为a-Al2O3,颗粒尺寸变化不大,仍在0.4~0.6 mm范围内;粒度1 mm左右的薄水铝石在1350℃下煅烧2 h尚不能完全转变为a相,并已出现明显烧结. 因此,以水热法制备的亚微米级薄水铝石晶体作为前驱体,经直接煅烧可以制备出分散性较好的亚微米级a-Al2O3粉体.

关键词: 水热法, 薄水铝石, a-Al2O3, 粉体, 粒度

Abstract: The influence of particle size of boehmite powder on the formation of a-Al2O3 powder during the subsequent calcination process was studied. Three kinds of dispersive boehmite precursor particles with nano, submicron and micron-scaled grain sizes were prepared by hydrothermal method. Crystalline phases and morphologies of the powders produced by calcination of boehmite at different temperatures were analyzed with XRD and the electron microscopy. The experimental results showed that calcination of 30~100 nm boehmite particles at 1200℃ for 1 h resulted in the formation of single-phase a-Al2O3, and the product powder consisted of vermicular particles. 0.4~0.6 mm boehmite particles were fully converted to a-Al2O3 by calcination at 1250℃ for 1 h, and the product powder consisted of porous plate-like particles in the same range of 0.4~0.6 mm in size. The product powder was still composed of a little proportion of transition alumina besides a-Al2O3 by calcination of 1 mm boehmite particles at 1350℃ for 2 h, and the particles were sintered severely. Therefore a-Al2O3 powder in the sub-micron size range with good dispersivity could be obtained by calcination of submicron-scaled boehmite powder prepared by hydrothermal method.

Key words: hydrothermal synthesis, boehmite, a-Al2O3, powder, particle size