2025 AIChE Annual Meeting

(298a) Effect of Moisture (2mol%) on CO2 Enhanced Desorption from Nano-Dispersed Na2o/Al2O3 for Direct Air Capture

Authors

Xiao Lin, Columbia university
Increasing carbon dioxide concentration has long been a problem that people have noticed. CO2 is an undesired byproduct when energy is produced, and its emissions have increased rapidly due to numerous developments since the era of the Industrial Revolution. The concentration of CO2 reached 414.7 ppm in 2023, and it is expected to increase further. Therefore, carbon capture technology will become an essential part of our lives to mitigate greenhouse gas emissions and reduce the level of CO2 concentration in the atmosphere.

This study demonstrates enhanced amount and rate of CO2 desorption at low temperature from nano-dispersed “Na2O”/r-Al2O3 using a low moisture (2 mol% H2O) content purge gas generated from the vapor pressure of H2O at 20 °C, = 17 mm Hg relative to a dry purge. Ni is added to catalytically hydrogenate the Na2CO3/Al2O3 precursor to highly active CO2 and Na2O/Al2O3. Multi-cycle aging tests conducted over 317 hours (60-cycles aging) and varying capture conditions confirmed the stability. This allows a decrease in energy consumption in desorbing the CO2. Figure 1a shows that a moist purge (orange) enhances the amount and rate of CO2 desorbed relative to a dry purge at lower temperature, and Figure 1b demonstrates moist conditions desorb more CO2 than dry at the same temperature.

Figure 1a shows that a moist purge (orange) enhances the amount and rate of CO2 desorbed relative to a dry purge at lower temperature, and Figure 1b demonstrates moist conditions desorb more CO2 than dry at the same temperature.