> In this case; how do they recombine the CO2 into more complicated hydrocarbons?
Fischer–Tropsch process.
> And if it’s energy negative, is it better to do this, or to use it to capture carbon?
It's obviously "energy negative", as it would be a violation of thermodynamics for it not to be, entropy being how it is. As far as doing it over carbon capture, I would be more interested in hearing your thoughts on why carbon capture would be a better alternative.
Fischer–Tropsch process.
> And if it’s energy negative, is it better to do this, or to use it to capture carbon?
It's obviously "energy negative", as it would be a violation of thermodynamics for it not to be, entropy being how it is. As far as doing it over carbon capture, I would be more interested in hearing your thoughts on why carbon capture would be a better alternative.