How do astronauts prevent the buildup of carbon dioxide inside the spacecraft?

Question

How do astronauts prevent the buildup of carbon dioxide inside the spacecraft?

In: Chemistry

Answer 1

CO2 Scrubbing is the process of removing CO2 from the air. Originally, I believe this was done using calcium oxide filters, which react with CO2 to form calcium carbonate. This consumes the calcium oxide, which is less than ideal. Modern systems use a similar system, but not with calcium oxide. Essentially, a material absorbs the CO2, and then is treated to remove the CO2 once the material has been moved to a sealed container, before it is pumped back out to absorb more. I’m uncertain how modern systems are treated to remove the CO2 from the absorber, but as an example, when calcium carbonate is heated up a lot it releases its CO2 and returns to being calcium oxide.