Supported Amine Sorbents under Temperature Swing Absorption for CO₂ and Moisture Capture

Abstract

Supported amines have been identified as potential regenerable sorbents that maximize capture of CO2 and water vapor while minimizing regeneration power requirements for long duration human space flight applications. In this study, the parameters governing the efficiency of the sorption and regeneration process under temperature swing absorption conditions were investigated. Desorption pressure (9−93 mmHg) and desorption temperature (30−60 °C) were identified as the most significant factors affecting capture in the supported amine system. Increasing the temperature of the desorption step permitted utilization of a weaker vacuum for removal of moisture and CO2, and thus reduced the energy requirements for desorption. A preliminary thermal energy analysis shows this system to use less than 25% of the energy required for regeneration of the zeolite sorbent system operated on the International Space Station.