The kinetics of CO hydrogenation over coprecipitated 36 wt% Co/Al2O3 was studied in a fixed-bed microreactor at atmospheric pressure. Intrinsic kinetic data were obtained in the initial rate region using four different CO concentrations and two different H-2/CO ratios over the 473-523 K temperature range. The surface carbide mechanism. with dissociative adsorption of hydrogen as the rate controlling step gives the most plausible kinetic model among the eight different models tested. C-1-C-4 production rates are found to be strongly influenced by temperature, and optimum C-1-C-4 hydrocarbon selectivity is obtained at 508 K. The activation energy for CO consumption and CH4 formation are calculated as 74 +/- 2 kJ mol(-1) and 84 +/- 2 kJ mol(-1) respectively.