Sol-gel process for obtaining pure and mixed oxide zirconia washcoats, useful as catalysts or catalyst supports

摘要

A process for obtaining pure or mixed oxide zirconia washcoats consisting of:preparing a zirconium solution in water at a concentration, formally expressed as ZrO2, equal or lower than 400 g/l, starting from a basic zirconium carbonate additioned of glacial acetic acid, and eventually preparing one or more solutions of the other oxides when necessary;preparing a sol of zirconium, eventually mixed to other metals, by a thickening agent;sucking the sol into the honeycomb channels in order to obtain the washcoats, with subsequent gelation with gaseous ammonia;ageing the so obtained gel;drying and calcining.