A flow reactor with the reactants heated by continuous CO2 laser radiation is proposed for studying the gas phase homogeneous reactions. Ethane pyrolysis yielding ethylene is considered as an example of such chemical process. For this process, a mode of 'energetic catalysis' is feasible, where increasing energy absorption in the volume is related with the increased content of target product. The mode of 'energetic catalysis' was implemented at transformation of laser energy into thermal power using the sensitization properties of ethylene. In the pyrolysis reaction zone, temperature measurements were made for a gas mixture in the laser radiation field with a power density up to 10(2) W/cm(2). The walls and windows were isolated from the high-temperature zone by argon feeding and configuration of the reactor. Three-dimensional calculation of the gas-dynamic reactants flows and their mixing made with the FLUENT software package showed the presence of the modes where reaction zone with a high content of C-2 hydrocarbons is localized in the center of reactor, which was confirmed by experiments. High values of ethane conversion up to 80 vol.% were obtained at nearby 53% selectivity for ethylene. (C) 2009 Elsevier B.V. All rights reserved.