Dual Function Materials Enabling Human Space Flight: Carbon Dioxide Capture and Conversion for Life Support on Crewed...

Area of Science:

• Materials Science
• Chemical Engineering
• Aerospace Engineering

Background:

• Accumulation of carbon dioxide (CO2) in spacecraft cabins poses a significant risk to astronaut health.
• Direct air capture of CO2 is vital for mitigating climate change on Earth.
• Current CO2 removal systems require dry air, increasing complexity and resource demands.

Purpose of the Study:

• To investigate the efficacy of dual function materials (DFMs) for capturing and converting CO2 from simulated spacecraft cabin air.
• To evaluate DFM performance under realistic, humid conditions relevant to human spaceflight.
• To assess DFMs as a potential recycling solution for CO2, producing water.

Main Methods:

• DFMs were tested for CO2 capture and conversion capabilities using gas mixtures simulating astronaut cabin air (1500-3000 ppm CO2).
• Experiments were conducted with both dry and moist air inlets to assess the impact of humidity.
• CO2 capacity and uptake rates were measured under varying conditions.

Main Results:

• DFMs demonstrated a nearly fourfold increase in CO2 capacity and a tenfold increase in uptake rates with moist air compared to dry air.
• The wet CO2 capture capacity of the DFM was found to be comparable to current state-of-the-art sorbents used on the International Space Station (ISS).
• Unlike ISS systems, DFMs maintain high performance in the presence of moisture, eliminating the need for pre-drying.

Conclusions:

• DFMs offer a promising, integrated solution for CO2 removal and recycling in spacecraft, converting CO2 into water.
• The superior performance of DFMs with moist air presents a significant advantage over existing technologies, simplifying system design.
• This technology has the potential to substantially reduce mass, size, power consumption, and complexity, enabling longer human space missions.