The conflict of interest is real. This is why I expect the same companies that produce the CO₂ to process it into fuel. Say, steelmakers need a lot of pure oxygen, this is why they sell the liquid nitrogen they produce along the way. Similarly they extract and sell a number of metals that occur in the input ores in low concentrations and are not worth mining by themselves.

Regarding Sahara, the things are sadly as you described. But large industries are usually in politically more stable areas.