Research has focused on dry reforming because it offers a sink for CO2 and relative to steam methane reforming produces a more desirable ratio of H-2 to CO for feed to a Fischer-Tropsch synthesis process. To form synthesis gas by dry reforming in a rapid, environmentally benign manner, a fluid-wall aerosol flow reactor powered by concentrated sunlight has been designed. Operating with residence times on the order of 10 ms and temperatures of approximately 2000 K, CH4 and CO2 conversions of 70% and 65%, respectively, have been achieved in the absence of any added catalysts. Methane to carbon dioxide feed ratios greater than unity were fed in order to prevent reaction of CO2 with the graphite tube. The carbon black particles formed by reaction were amorphous carbon black with a primary particle size of approximately 20-40 nm.