[Synaesthesia]

>I have to wonder if human kind will need to find some way to convert CO2 to pure carbon for storage as a climate control measure.

We have! They're called plants. Any other method uses far too much energy to be able to do at the scale we need.

Plants do capture carbon. As long as they don't burn subsequently, this isn't released again as CO2.

[elihu]

I'm not an expert in this area, but I was under the impression that any form of decomposition causes most of the carbon in the plant to re-enter the atmosphere as carbon dioxide. Thus using plants to sequester carbon isn't just a matter of planting more trees; you actually have to pay attention to what happens when the tree dies.

[Synaesthesia]

Some of it does, but a lot becomes part of the soil. (Source:https://blogs.ei.columbia.edu/2018/11/27/carbon-dioxide-remo... ) Coal and Oil were once plants and organisms, examples of such carbon sequestration.

[frosted-flakes]

I was under the understanding that the plants and trees that became coal and oil didn't decompose because at the the time, nothing had evolved yet that could consume it. So it just collected on the ground with new stuff growing on top of it, forming this compressed mass of underground carbon fuel that we were able to exploit millions of years later. It could never happen today because all of that plant matter would rot before that could happen, because of the presence of bacteria that can break down plant matter.

[orwin]

Now, if we could somehow remove ligogen from wood, we would have pure carbon, ignifuge building material. This would do a lot for the planet.

[bmn__]

related: http://enwp.org/hydrothermal_carbonization