Carbon dioxide sequestration at elevated temperature by pressure swing adsorption

Modeling and simulation of CO₂ capture from flue gases of coal fired power plant at high temperature are presented. The work employed a 19% potassium and 1% sodium hydrotalcite adsorbent, for which CO₂ capacities in excess 0.84 mol/kg were measured at temperature of 575 K. Elution profiles from a pressure swing adsorption (PSA) unit also enabled analysis of adsorption and desorption process. A cyclic and multibed process for the continuous capture of CO₂ was proposed. A mathematical model for the CO₂-19% potassium and 1% sodium hydrotalcite adsorbent system, based on measured equilibria and kinetic data, was used for the assessment of the process in terms of CO₂ product purity and recovery.