High Capacity Thermally Regenerated Supported Amine Sorbents for CO ₂ Removal 2004-01-2443

In this study, a parametric examination of the main factors affecting cyclic CO₂ absorption into supported amine sorbents has been conducted. A bench-scale test apparatus and Taguchi statistical design of experiments were used to assess the importance of cycle time, inlet CO₂ concentration, residence time, humidity, absorption temperature, desorption temperature and desorption pressure on cyclic CO₂ capacity. Two amine sorbents were considered: TEPAN and modified E-100. Amine decomposition, amine oxidation, and the effects of amine chemical composition were also examined. For typical ranges of system variables found on-board the space shuttle orbiter, results indicated that desorption pressure over the range of 25–85 torr, desorption temperature over the range of 50–60°C, absorption temperature over the range of 20–30°C, and CO₂ concentration over the range of 6–9 mmHg were the most important variables affecting cyclic CO₂ removal capacity. Cycle time, dew point, and residence time were found to be insignificant over the ranges considered. Desorption pressure was found to account for 61% of the variation in the cyclic capacity of CO₂ for TEPAN and 82% for E-100. Desorption temperature and absorption temperature accounted for 19% and 6%, respectively, for TEPAN. Desorption temperature and inlet CO₂ concentration accounted for 8% and 9%, respectively for E-100.