Carbon capture, utilization, and storage (CCUS) technology represents the fossil fuel industry’s last stand. Hawking expensive, speculative technology to suck CO2 out of the air and store it underground — rather than transitioning away from fossil fuels — enables immensely profitable oil companies to continue business as usual while presenting themselves as part of the solution to the climate crisis.
Thermodynamics does not prohibit a reaction in which carbon is liberated from complex hydrocarbons and incorporated into some other compound which can be conveniently stored as an inert powder, with a net gain of energy.
Carbon capture: Not completely ruled out by the laws of physics, in theory.
The point is that it will cost more energy capturing it, than you got emitting it.
Edit: if you had to use fossil fuels for energy in the first place, you won’t have the energy to spare to capture CO2 back when you’ve abandoned fossil fuels.
That is not always true.