A coprecipitation method has been developed and modified for the preparation of nickel-alumina catalysts having metal loadings in the 0-25 wt% Ni range. The effect of metal loading on CO2 adsorption was investigated under isothermal chromatographic conditions using an elution technique in the temperature range 483-533 K. Average enthalpies of adsorption were determined using the isosteres obtained from the experimental adsorption isotherms. The isotherms were also fitted to the Langmuir equation for the evaluation of adsorption equilibrium coefficients, Gibbs free energies, average adsorption enthalpies and entropies.