When carbon burns in oxygen a great deal of energy is released. This is energy that was stored in the electronic arrangements and energy levels of electron orbitals in the carbon and oxygen atom. To remove carbon from CO2 requires energy, in fact, the same amount of energy we got when we burned carbon in the first place. This is not impossible, plants do it all the time, using photosynthesis. The energy comes from the sun, in the form of sunlight. That energy was originally created by thermonuclear fusion, a process that involves hydrogen nuclei in the sun's core being forced together by gravity to form helium.
There is only one way to stop climate change and global warming., and that is to stop making CO2 by burning carbon in the atmosphere. There is no magic bullet that will allow us to get around this by some clever tech financed by enlightened investors. Either we find a way of creating energy that doesn't involve burning fossil fuels, or we learn to live without having to use so much energy.
The world is producing 37 billion metric tons of CO2 every year. Much of this is stored in plant tissue, marine shells, dissolved in sea water, or trapped as carbonates in rock strata. The excess goes into the atmosphere.
There is no easy way out.
The general public knows the chemical compound of carbon dioxide as a greenhouse gas in the atmosphere and because of its global-warming effect. However, carbon dioxide can also be a useful raw material for chemical reactions. A working group has now reported on this unusual application. They are using carbon dioxide as a raw material to produce graphene, a technological material which is currently the subject of intense study.
This is true. But it is also irrelevant. It is a distraction to persuade us we do not have a problem, and we should keep on as before, burning coal and oil. Even if we could use such a process, and even if it could be powered by some source of energy not generated by burning fossil fuels, what the hell would we do with 37 billion tons of graphene?
Besides, we already have a way of removing excess CO2 from the atmosphere. Its called plants and molluscs. And they are both free.