This is mostly a good-news story, but perhaps not quite as good as the
hyped-up press report/1/ would have you believe.
1) CO₂ in the atmosphere is a big problem.
2) Getting to "net zero" carbon emissions "eventually" is not good
enough. We need to get to /net negative/ muy pronto.
3) Most schemes for carbon sequestration make no sense. They violate
the second law of thermodynamics or summon sense or both.
4) There is however hope for mineralization, i.e. turning silicate
minerals into carbonate minerals (plus leftover silica). This is
allowed by thermodynamics. When it happens naturally, it's called
"weathering" of the rocks. Alas, natural weathering is too slow by
orders of magnitude. There is hope of making the reaction go faster.
You can change the kinetics without changing the thermodynamics.
5) The recent paper by Yuxuan Chen and Matthew W. Kanan/2/ might be a
stepping stone on the path to a solution. Or it might not. As it
stands, it is not a complete solution. AFAICT it is still a couple of
miracles short of solving the whole problem.
6) I'm not complaining. I've spent many years persuading people to
share their partially-baked ideas. Sometimes I can help, perhaps
directly or (more likely) by referring them to somebody else. To say
the same thing the other way, if you wait until the project is
completely finished, it's too late for anybody to make constructive
suggestions.
7) In passing, the paper also contains a useful critique of other
approaches to carbon sequestration.
8) As usual, the press release/1/ spins the work as the greatest
invention since the wicker basket. However, if you read the actual
paper,/2/ you see a couple of gotchas. For starters, the first step in
the process /releases/ CO₂. They gloss over this, as if they had a
good scheme for sequestering it, which they don't. The other gotcha is
that the process requires high temperatures. The first step
(calcining the calcium minerals) could conceivably (albeit not easily)
be done with a solar cooker, using no fuel at all. However, alas, the
second step requires getting things yellow-hot (1200 °C), i.e. quite a
bit hotter than red hot. This can be achieved by burning fuel in pure
oxygen. It "might" be achievable using electric heating, but this
approach is unproven (to say the least).
In other words, they have issues with the carbon budget /and/ with the
energy budget.
Bottom line: These guys don't have a process that can be used at
scale, and they are a couple of miracles shy of having one. Even
so, I'm not complaining. This work might inspire somebody to come
up with an actual practical scalable solution.
Postscript: If you have students who want to know what real research
looks like, steer them to this paper. Ask them to read it and identify
the strong points and weak points (i.e. open issues).