P-XYLENE YIELD IN FLUID CATALYTIC CRACKING PRODUCTS

Both direct dealkylation of feed aromatics and hydrogen transfer chemi stry contribute to the production of para-xylene in fluid catalytic cr acking gasoline products. Based on laboratory scale FCC riser testing, it was found that catalysts containing high rare earth and low matrix activity are the preferred catalysts for high p-xylene yields in flui d catalytic cracking products. Aromatic feedstocks yield higher p-xyle ne than paraffinic feeds. Catalyst or feed change did not alter the di stribution among the three xylene isomers. p-Xylene yield increases wi th conversion, but the o,m,p distribution does not change much with co nversion.