[Puradolia]

There's no reason to do that. You do not want to create more methane, and the possibility of even a trickling of it getting into the atmosphere. This methane to methanol is purely to get rid of the methane we produce, and hopefully the methane stored in the atmosphere. We've got plenty of hydrogen, it's one of the most common elements (iirc) in the known universe, but to convert some into methane? Hydrogen is clean, and then make it toxic methane? It's much better to just use the hydrogen as fuel. I remember seeing an article one time about a method to convert hydrogen into fuel, and so it's much better to do it that way. Though how costly or doable on a mass scale either conversion is, we don't know yet.

[labster]

Methane is not toxic, in fact it’s frustratingly inert. Leading to long atmospheric residence time in decades. Unless you meant to type toxic methanol, which is true, but it’s not that toxic. Just don’t drink the wood alcohol, okay?

I think the plan is to produce methane from hydrogen on Mars for the return trip on Starship. Kind of a niche case, though.

[TimJRobinson]

This would be an alternative source of methane rather than getting more from the ground. If we could recycle the carbon in the atmosphere + hydrogen from water we could use this wherever methane is used currently without needing to make new vehicles / aircraft etc that run on hydrogen.

This is a good article about it: https://caseyhandmer.wordpress.com/2022/07/22/were-going-to-...

[Schroedingersat]

Hydrogen is incredibly dangerous and bulky. Using it where you create it works well enough, but without some breakthrough in metal hydride storage or similar it's starting to look like a poor choice even against batteries if you want to move your energy around.

Stuff that can store as a liquid opens a lot of possibilities, although this probably means ammonia most of the time.