The preparation method of boehmite

The preparation method of boehmite:

As one of the most important precursors of alumina, boehmite AlOOH is mostly prepared by the neutralization reaction of aluminum salts or the hydrolysis reaction of aluminum alkoxides. E.g:

1. Hollow spherical boehmite was prepared with Al(NO3)3·6H2O and sodium citrate in water-acetone system.

2. Using AlCl3·6H2O as raw material, the bundled particles composed of boehmite nanofibers were synthesized in ethylene glycol system.

3. Using AlCl3·6H2O as reactant, three-dimensional sea urchin boehmite assembled by nanorods was obtained in ethanol-water system.

The non-uniformity of the microscopic morphology of the powder aluminum hydroxide obtained by the direct hydrolysis method of aluminum powder determines the difference in its crystal structure, and the quality of the preparation of high-purity alumina usually fails to meet the requirements. Aluminum is prepared into pure boehmite, which is conducive to the synthesis of metastable γ-Al2O3, and finally forms thermodynamically stable α-Al2O3 through the metastable transition phase.

The hydrothermal method has become a research hotspot due to its advantages of simple operation, strong controllability and environmental friendliness, and is known as the most promising method on the road of green synthesis.