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A method for characterizing the high-pressure CO₂ adsorption kinetics of potassium-modified hydrotalcite at elevated temperatures based on a modified static bed is proposed. The pressure drop of the adsorption tube with time was measured by a series of high-sensitivity pressure sensors to calculate the CO₂ adsorption curves of the adsorbent. The concept of a hot/cold spot is introduced to eliminate the temperature deviation caused by the dead volume of the pipelines and the temperature disproportion in the tubes. As compared to conventional characterization methods such as thermal gravimetric analysis and fixed bed testing, the proposed method avoids the displacement effect, making it possible to obtain actual adsorption curves above atmospheric pressure. The effect of adsorption temperature (300–450 °C) and CO₂ partial pressure (0.1–2 MPa) and a reversible adsorption isotherm with 30 min adsorption …