Aggregate of cristallites of cerium oxide, process for obtaining it and use in the reduction of combustion residues

摘要

Ceric oxide crystallite systems capable of catalysing a far-reaching combustion of hydrocarbon fuels, especially heavy ones (fuel oil, diesel fuel). This aggregate is defined in that its largest dimension is between 50 ANGSTROM (5 nanometres) and 10,000 ANGSTROM (1,000 nanometres), preferably between 100 ANGSTROM (10 nanometres) and 5,000 ANGSTROM (500 nanometres) and in that the size of the crystallites, measured by the Debye and Scherrer technique, is between 50 and 250 ANGSTROM (5 to 25 nanometres), preferably from 100 to 200 nanometres. Application to the purification of exhaust gases.