Zinc aluminate, precursor composition of a zinc aluminate, processes for preparing an aluminate and treating gases, catalytic system and use of an aluminate

摘要

"ZINC ALUMINATE, PRECURSIVE COMPOSITION OF A ZINC ALUMINATE, PROCESSES FOR PREPARING AN ALUMINATE AND TREATING GASES, CATALYTIC SYSTEM AND USE OF AN ALUMINATE". The present invention relates to a zinc aluminate which is characterized by the fact that after calcination at 800 ° C, 8 hours, it has a specific surface of at least 85 m² / g. The invention also relates to a precursor composition of this aluminate. The process of preparing the aluminate and the composition comprises the following steps: a salt, a sol or a zinc alkoxide and an aluminum alkoxide are placed in a solvent medium; the mixture thus formed is hydrolysed by adding excess water to the aluminum alkoxide; the formed precipitate is recovered and eventually dried, thereby obtaining the precursor composition; if so, the said precipitate is calcined, thus obtaining the aluminate. Finally, the invention relates to the use of aluminate in a car exhaust gas treatment process.