EFFECT OF NITROGEN-COMPOUNDS ON CRACKING CATALYSTS

In a paper of the same title, Fu and Schaffer reported on the poisoning effects of more than 30 individual nitrogen and aromatic compounds on cracking catalysts. A significant outcome of their study was a database on the relative poisoning potency of a variety of nitrogen compounds. On the basis of the database, this study was aimed at correlating the poisoning power of nitrogen compounds with their structures. For each compound, we determined 24 structural variables; of these, the dominant ones were identified by a chemometric technique. This provides a basis for developing a simple nonlinear correlational model for practical applications. It is shown that the poisoning power of a nitrogen or aromatic compound is primarily determined by a balance between its heaviness/size and basicity. The former may be measured by molecular weight, while the latter by proton affinity.