催化学报

催化学报 ›› 2006, Vol. 27 ›› Issue (9): 805-809.

• 研究论文 • 上一篇    下一篇

SB粉水热分解铝酸钠溶液制取大孔容高比表面拟薄水铝石

蔡卫权   

  1. 武汉理工大学化学工程学院, 湖北武汉 430070
  • 收稿日期:2006-09-25 出版日期:2006-09-25 发布日期:2010-10-28

Preparation of Pseudoboehmite with Large Pore Volume and High Specific Surface Area from Sodium Aluminate Solution by Hydrothermal Precipitation Using SB Po

CAI Weiquan*   

  1. School of Chemical Engineering, Wuhan University of Technology, Wuhan 430070, Hubei, China
  • Received:2006-09-25 Online:2006-09-25 Published:2010-10-28

PDF

839

被引次数

22

摘要： 以德国Condea公司用有机醇铝法生产的拟薄水铝石SB粉为晶种,采用水热分解铝酸钠溶液结合乙醇分散洗涤种分产物的方法制得了大孔容高比表面拟薄水铝石. 研究了铝酸钠溶液组成(Al2O3浓度和苛化系数)以及晶种循环使用次数等条件对溶液分解率、 Na2O析出率和种分产物孔体积、孔径分布、比表面积以及钠含量等物化性质的影响. 研究表明, 在晶种比为1.0, 温度为125 ℃的条件下用SB粉分解铝酸钠溶液(Al2O3含量为100～140 g/L, 苛化系数为1.30～1.45), 3 h后溶液分解率可达30%左右,而SB粉连续循环使用3次所得产物的孔容和比表面积分别达到0.84 cm3/g和213.6 m2/g, Na2O含量在0.3%以下,部分性质甚至超过了SB粉的技术指标. 该方法为从廉价的铝酸钠溶液制备高附加值的拟薄水铝石提供了一条新的可供选择的路径.

关键词: 铝酸钠溶液, SB粉, 水热晶种分解, 拟薄水铝石, 大孔容, 高比表面积

Abstract: Pseudoboehmite with large pore volume and high specific surface area was successfully prepared by hydrothermal precipitation of sodium aluminate solution using SB pseudoboehmite (from Condea, Germany) as the seed, combined with dispersing and washing the precipitate with ethanol. Effects of the composition of the sodium aluminate solution (concentration of Al2O3 and molar ratio of Na2O/Al2O3) and the precipitation time on the precipitation yield of Al2O3 and Na2O and physico-chemical properties of the precipitates such as pore volume, specific surface area, and Na content were studied. When the sodium aluminate solution with Al2O3 concentration of 100-140 g/L and Na2O/Al2O3 molar ratio of 1.30-1.45 was used, about 30% precipitation yield of Al2O3 was obtained at 125 ℃ with a low seed ratio of 1.0. The obtained pseudoboehmite has a large pore volume of 0.84 cm3/g, a high specific surface area of 213.6 m2/g, and a low Na2O content less than 0.3% after the third precipitation cycle, and some of its properties are even superior to that of the SB powder. This study provides an preparation route for high value pseudoboehmite from the low-cost sodium aluminate solution.

Key words: sodium aluminate solution, SB powder, hydrothermal seed precipitation, pseudoboehmite, large pore volume, high specific surface area