Chapter 6B - Aerogel Synthesis as an Improved Method for the Preparation of Platinum-Promoted Zirconia—Sulfate Catalysts

Abstract

The aerogel synthetic method reported seems to represent a simple, easily accessible synthetic procedure for the preparation of Pt/ZrO2-SO4 catalysts, because everything can be done in one pot without the use of any special equipment. The specific conditions used for solvent evaporation, according to the aerogel synthetic procedure, are very stringent with respect to the determination of the analytical properties of the materials. This leads to a "homogenizing" effect with the removal of the "excess" sulfate and yields a constant surface concentration. In fact, the materials prepared have essentially the same amount of sulfate and the same surface area independently of the presence of platinum and the starting amount of sulfate. The morphology of the materials is predetermined by the solvent evaporation procedure. The crystal phase composition, the surface area, and the particle size of zirconia are essentially the same both before and after calcination and independently of the presence of platinum.