COMPOSITION BASED ON OXIDES OF ZIRCONIUM, CERIUM, NIOBIUM AND TIN, PREPARATION PROCESSES AND USE IN CATALYSIS

摘要

The composition of the invention is based on oxides of zirconium, cerium, niobium and tin in proportions by weight of oxide of between 5% and 50% for cerium oxide, 5% and 20% for niobium oxide, 1% and 10% for tin oxide and the remainder being zirconium oxide. The composition may be used in a catalytic system for an SCR-type process for treating a gas that contains nitrogen oxides (NOx).