Mechanosynthetic carbon dioxide splitting
From apm
The application of atmospheric CO2 removal (see: carbon dioxide collector unit) should give a strong incentive to make oxygen the next element of interest in the direct path research. Mechanosynthetic water splitting is needed too here.
Research needed: How needs the basic nine member diamondoid mechanosynthesis toolset be extended to be able to rip CO2 apart (and use the oxygen then)?