Feeding a dispersed cloud of powder into an aerosol flow reactor, particularly on a laboratory scale. presents challenges. In this study, a fluid bed feeder was developed. With this feeder, fluidizing gas and brass milling media were the key means to disperse and break apart particle aggregates. Particle size distributions were measured with a laser imaging system and the dispersing ability of the feeder characterized by the result of statistical fits. Statistical results from a spinning wheel feeder, which uses primarily mechanical shear to disperse particles, was also compared with those from the fluid bed feeder to see which appeared to disperse powder the best. The results indicated that a fluidized bed feeder is likely a superior feeder to provide dispersed particles into a reactor. Additionally, the amount of mass fed versus time from the fluid bed feeder was measured under a variety of conditions. Two distinct mass feeding regions were observed and analyzed. (c) 2009 Elsevier B.V. All rights reserved.