Elle passe en revue le développement et le perfectionnement The catalytic conversion of hydrocarbons has revolutionized des catalyseurs de cracking employés dans ces the petroleum refining industry within the procédés. On y a joint une description d'une réalisation-type past decade to the extent that well over fifty per cent du procédé Houdriflow de cracking catalytique, of the total capacity of conversion processes today parce que ce procédé a été mis au point depuis is of the catalytic type. This paper recounts the history of catalytic à une raffinerie hypothétique pouvant charger cracking from its beginning in the 1920's to thc present 25000 barils de brut Irak par journée de marche, day. Reforming cracking process is included, because this process has The catalytic conversion of naphtha and the higher been perfected since the last World Petroleum Congress boiling distillate fractions of crude oil into fuel for meeting. Typical yield and economic data are internal combustion engines has already exceeded given, which show the application of Houdriflow 50% of the cracking capacity in the United States, catalytic cracking to a hypothetical rei inery charging and will have predominantly supplanted the other 25,000 barrels per stream day of Iraq crude. Basically, the reason for this rapid replacement La conversion catalytique des hydrocarbures a révolutiond of the previously typical refinery operations l'industrie du raffinage du pétrole au is the inherent over-all economy of this kind of processing, cours des dix dernières années à tel point que bien coupled with the high octane number of the plus de cinquante pour cent de tout ce qui se fabrique motor fuel and the abolishment of viscous tarry aujourd'hui par procédé de conversion s'obtient par residues.