Steam reforming of propane-methane mixture into methane-rich gas was studied in a fixed-bed continuous- flow reactor in a temperature interval of 150-325 degrees C under atmospheric pressure over Ni-based catalyst. It was found that the catalyst had good performance under low steam-to-carbon ratio of 0.39-0.58 and provided equilibrium product distribution at GHSV = 670-3100 h (1). Macrokinetic modeling of the experimental data obtained was performed in the framework of isothermal plug-flow reactor model. For the first time the two-step macro-kinetic scheme was suggested, that includes the reactions of irreversible propane steam reforming (first-order on propane): C3H8 + 6H(2)O -> 3CO(2) + 10H(2) with activation energy 112 kJ/mole and reversible CO2 methanation (first-order on hydrogen): CO2 + 4H(2) reversible arrow CH4 + 2H(2)O with activation energy 50 kJ/mole. It was shown that the proposed scheme describes quantitatively all the experimental results. (C) 2014 Elsevier Ltd. All rights reserved.