When alumina and FCC catalysts were mixed, the fluidity of the mixture was significantly lower than that of each particle type alone. A significant amount of dried particles adhered to the inner wall of a column, and channeling was observed. The main cause of these phenomena was found to be symmetrical electrification due to mutual friction between the two types of particles. This caused agglomeration of particles and the decrease in the fluidization quality. Adding 4 wt% of water to the pores of the particles reduced the influence of the electrostatic force. Increasing the bed temperature above 523 K also improved the fluidity of the beds.