The technique of Laser Soot-Mie Scattering (LSMS) is utilized to study the effect of fuel volume and ring circulation on the formation and evolution of soot in reacting vortex rings. Propane reacting in air at atmospheric conditions under microgravity is considered. Diffusion flame-vortex ring interaction contains the fundamental elements of flow, mixing, combustion, and soot processes found in practical turbulent reacting flows. Flame-vortex interaction allows these fundamental processes to be studied under more controllable conditions than direct investigation of these elements in practical flames. Soot concentration was found to be higher in regions of lower strain and along the periphery of the reacting vortex rings. No soot was found inside the reacting vortex ring, however soot was enclosed inside the flame zone. Future quantification of these soot concentrations will allow researchers to test their models of soot against these experimental results. In addition, flame-vortex interaction provides an attractive configuration for numerical simulations due to its simplicity than a full calculation of turbulent reacting flows, and yet containing the fundamental processes found in practical reacting flows.