Air pre-purification is an important process for industrial air separation with cryogenic distillation method. This process is typically realized by pressure swing adsorption or temperature swing adsorption. H2O and CO2 are the two major components to be removed among the contaminants. In this paper, we establish a mathematical model describing the mass and heat balances in the adsorption bed, and the double-component adsorption/desorption equilibriums of H2O/CO2 on alumina F200. To conduct desorption performance analysis, a one-cycle process consisting of feed, blowdown, and purge step under different operating conditions, such as feed/purge pressure ratio and regeneration temperature, is numerically studied. The effect of heat on the desorption performance of H2O and CO2 is investigated by changing the purge gas temperature within 30 °C to 200 °C under feed/purge pressure ratios of 6:1.1 and 10:1.1, respectively. Detailed results of the H2O and CO2 adsorption/desorption behaviors in the bed are demonstrated. The mass and heat transfer characteristics during desorption are also analyzed. Suggestions on the optimization of the heating temperature and duration of purge gas are also proposed.