The CO2 adsorption equilibria of the honeycomb zeolite beds consisting of MS-13X or MS-4A were determined from breakthrough curves for various CO2-N-2 mixtures, and the fitness of the Dubinin-Astakhov equation (Dubinin MM, Astakhov VA. Description of adsorption equilibria of vapors on zeolite over wide ranges of temperature and pressure. In: Flanigen M, Sand LB, editors. Molecular sieves zeolite II. Washington: American Chemical Society, 1971) to the obtained data was examined. The Langmuir approximation to the Dubinin-Astakhov equation was also proposed and its validity was discussed. It is found that the CO2 adsorption equilibria of the examined honeycomb zeolite beds well correlate with the Dubinin-Astakhov equation and that the evaluated Langmuir parameters can be represented by an exponential function of the temperature,