This is all from memory: Diethyl-ammonia works but is energy intensive to regenerate. Zeolites require less energy to regenerate but also absorb water. Some zeo

This is all from memory: Diethyl-ammonia works but is energy intensive to regenerate. Zeolites require less energy to regenerate but also absorb water. Some zeolite crystal structures might exist that are less hydroscopic, but have yet to be discovered. MOFs are like zeolites, but easier to fine tune and some good CO2 absorbers that are also not too hydroscopic have been identified. MOFs have some serious stability issues.