In this study, a commercial activated carbon was assessed as adsorbent for post-combustion CO2 capture. The breakthrough adsorption experiments were conducted in a fixed-bed column with simulated flue gas of 12% CO2. The effects of feed flow rate and adsorption pressure on breakthrough time and CO2 adsorption capacity were evaluated. The column efficiency was introduced to estimate the percentage of the utilization of the bed adsorbent capacity. At a higher flow rate, the breakthrough time, breakthrough capacity and column efficiency decreased. Conversely, increasing adsorption pressure was favorable to CO2 adsorption by the increase in breakthrough time, CO2 adsorption capacity and the column efficiency. During the experiments, temperature changes were detected at three positions inside the column to track the movement of breakthrough front.