| Popis: |
Selecting the appropriate catalyst deactivation method is critical in predicting commercial FCC catalyst performance by lab-scale performance testing. One of the most accurate ways of mimicking a commercial equilibrium catalyst is through cyclic deactivation (CD), in which a catalyst is exposed to cracking and regeneration cycles, using a feed with enhanced metals content. In spite of the success of this technique in matching commercial metals deposition profiles and “potencies”, there are still shortcomings in simulating the deleterious effects of contaminant iron on catalyst accessibility, as measured by the Akzo Accessibility Index (AAI.) A modified CD method is presented that utilizes a lower steam partial pressure in regeneration that produces realistic catalyst accessibility losses with added iron. Two catalysts have been deactivated by a variety of methods, demonstrating the effect on AAI of different steaming conditions and metals levels. Performance testing results of these catalysts are compared with those of equilibrium catalysts. |
