| Abstract
| - This study was conducted in an effort to learn more about the roles of feedstock and catalystin the distributions of sulfur and nitrogen in liquid products after catalytic cracking. Ahydrotreated coker gas oil, a hydrotreated deasphalted oil, a virgin gas oil, all derived fromCanadian oil-sands bitumen, were catalytically cracked in a fluid bed microactivity test (MAT)unit with two commercial catalysts. These were the equilibrium catalysts, bottoms-cracking andoctane-barrel catalysts, respectively, both containing active matrixes. The cracked liquid productswere analyzed for sulfur and nitrogen distributions with boiling point, from which the sulfurand nitrogen contents of gasoline, light cycle oil (LCO), and heavy cycle oil (HCO) fractions weredetermined. Variations of concentrations in each product cut with conversion were discussed,along with the hydrogen transfer indices of catalysts and the hydrogen yields of feeds. The overalldistribution of feed sulfur in cracked products, and the relationship of the sulfur content of feedwith that of LCO, confirmed the findings reported in the literature. The same three feeds werealso cracked with the octane-barrel catalyst in a riser pilot plant. The sulfur and nitrogenconcentrations in each product fraction from MAT were found to be in reasonably good agreementwith those obtained from the riser pilot plant operation. Results from this study will provide thescientific community with a better understanding about the cracking chemistry of sulfur- andnitrogen-containing species in gas oils under different test environments.
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