Abstract: The micro activity of FCC catalyst used as adsorbent for removing SOx and NOx in flue gas (adsorbent-catalyst) was evaluated using light diesel distillate and n-hexadecane as feeds respectively, and the feasibility of reuse said adsorbent-catalyst in FCC unit was discussed. Test results showed that the micro activities of used adsorbent-catalysts were equal or even a bit higher than those of the reference catalysts. Further evaluation was performed on ACE unit using VGO feed and composite catalyst based on catalyst MLC-500. Results showed that within a mass fraction of used adsorbent-catalyst in the range of 5% to 10%, the feed conversion and coke yield increased with the increase of adsorbent-catalyst amount, yet the increment of coke selectivity was just half of that of the fresh catalyst.

Key words: catalytic cracking, flue gas, adsorbent, catalyst, activity