Elaboration of boehmite nano-powders by spray-pyrolysis

Boehmite (γ-AlOOH) synthesis have been investigated using a spray pyrolysis (SP) device starting from a stable sol of Al-tri-sec-butoxide peptized by nitric acid. Free spherical particles from 100 to 500 nm have been elaborated. Particles sub-structure is made of nano-crystalline boehmite with very small average crystallite size (one crystal cell along the b axis). The nano-crystalline boehmite synthesized by SP at low temperature (200 °C) is spontaneously dispersible in water without any surface treatment. Boehmite powder may be transformed to transition γ-alumina by heat post-treatment. Powders of sub-micrometric and spherical γ-alumina particles may also be synthesized by SP at 700 °C.

Boehmite (γ-AlOOH) have been synthesized using a spray pyrolysis (SP) device at T = 200 °C, from a stable sol of Al-tri-sec-butoxide as precursor. The free spherical particles (100–500 nm in size), made of nano-crystalline boehmite, are spontaneously dispersible in water.Figure optionsDownload as PowerPoint slide