[01] M. A. Mustafa, Department of Chemical Engineering, University of Khartoum, Khartoum, Sudan. [02] Mert Atilhan, Department of Chemical Engineering, Qatar University, Doha, Qatar.

Changes in structure of samples of fresh and spent catalyst are studied for a commercial residue fluid catalytic cracking unit. Quantitative estimates of micropore volume, surface area and pore size distribution are obtained based on Barrett-Joyner-Halenda (BJH), Brunauer-Emmett-Teller (BET), Dollimore-Heal (D-H), Density Functional Theory (DFT), Freundlich, Temkin, t-plot and Langmuir methods. In addition to the insight provided, of the molecular scale crystalline pores, the complementation of SEM-EDS has revealed structural and surface information on the morphology of the particles. A clear degradation of FCC catalyst is evident with a significant reduction in pore volume and surface area. The cause of deactivation is clearly due to fouling, poisoning, dealumination and possibly sintering.

Fluid Catalytic Cracking, Deactivation, Catalyst, Characterization

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