Preparation of Superfine Aluminum Hydroxide Fine Powder by Spontaneous Nucleation

Superfine aluminum hydroxide fine powder with sheet-like particle in the range of dozens of nanometers to a few micrometers were prepared in high yields(90%) by spontaneous nucleation which is decompose under 45°C after cooling and diluting the solution of NaAlO 2 abruptly without seeding .The influence of the concentration of NaOH when decomposing on the distribution of particle size were investigated .The vacuum freezing drying oven with vacuum(11pa) and freezing(-45°C) were used .The study showed that the optimum is under the concentration of 2.69 mol/kg.Moreover,the powders dried by the vacuum freezing drying oven has no agglomerative phenomenon and the particle size are much smaller then other ovens.