Abstract
Porous alumina with uniform microstructure was prepared using needle-like boehmite particles. A procedure for improving its thermal stability was examined. Uniform, needle-like boehmite particles were synthesized using a hydrothermal procedure. Porous boehmite was prepared using vacuum filtration of boehmite aqueous suspension. Porous alumina was prepared by heat treatment of the porous boehmite. During heat treatment at 1200°C for 2 h, the specific surface area of the porous boehmite decreased to about one-twentieth (8 m2/g) of the as-prepared porous boehmite. To improve the thermal stability of the porous alumina, La addition to the porous boehmite surface was conducted merely by filtrating La aqueous solution using the porous boehmite itself. The porous alumina with 1.1 mol % of La showed specific surface area of 46 m2/g, even after heat treatment at 1200°C for 2 h.
