METHOD OF MAKING MESOPOROUS ZIRCONIUM-BASED MIXED OXIDES

摘要

Mesoporous, zirconium-based mixed oxides and a method of making the same comprises: injecting a polyvalent metal-containing solution into an electrolyte solution to form a mother liquor; forming a precipitate; aging the precipitate in the mother liquor to form the mixed oxides; washing the mixed oxides with an aqueous medium; drying and collecting the mixed oxides. The pH of the electrolyte solution exceeds the isoelectric point for zirconium-based mixed oxides. The mixed oxides exhibit a single particle size distribution, improved Ce02 reducibility in the presence of Rhodium, a decrease in surface area after calcination (800-1 100°C) that is not more than 55%, and a tetragonal/cubic structure after calcination. After calcination at 1 100°C for 10 hours in air, the mixed oxides exhibit a surface area 25 m2/g, a pore volume 0.20 cm3/g, an average pore size 30 nm, and an average crystallite size between 8 -15 nm.