Geochemical Carbon Capture

[Keith Lofstrom]

In an email to me, Simon Field pointed out that geological carbon capture
is actually GEOCHEMICAL carbon capture. Using electricity and geothermal
heat to CHEMICALLY COMBINE basalt and CO₂ into permanent carbonate rock,
instead of pumping the gas into cavities in the rock and hoping the gas
never leaks out.s

Thank you, Simon, for that information, which helped me find the
Climeworks website; https://climeworks.com/

Climeworks is a Swiss company operating a 4000T/y carbon sequestration
system in Iceland. Another was planned in Washington State, but that
other company failed.

GEOCHEMICAL carbon capture is endothermic; heat and electricity input
is required to chemically transform the basalt, perhaps 444 kWh of
electricity and 1333 kWh of heat per tonne of CO₂ transformed.
Humanity is currently emitting about 40 BILLION tonnes of CO₂ per
year, which would require about 500 GW of electric power and
1500 GW of heat power to sequester CO₂ as fast as we make it.

A factor of 10 million scale-up from the Climeworks experiment.

My no-doubt-flawed conclusions here: http://wiki.keithl.com/CarbonCapture

----

I am working on another webpage/brainfart, about the consequences
of "burn every scrap of geological carbon".

If we keep CO₂ BELOW current levels, the Earth could sustain life
for 200 million years, until the Sun evolves hot enough to bake
our planet. If we burn ALL the carbon at current rates, humans
and nature can still function in >1000 ppm carbon and a few more
degrees of environmental temperature. The excess heat is mostly
heating seawater, expanding the ocean's volume at square law
rates.

In a millennium or less, wiping out most macroscopic species
(like mammals and vascular plants) that cannot evolve radically
different metabolisms fast enough.

Thermal coefficient of expansion of seawater is quite low at
current near-freezing bottom temperatures, but increases square
law above that. Another "fell off a cliff, haven't hit the
ground yet" encouragement to delay solving the problem.

The world as we know it is surprisingly benign and adaptive,
but that adaptation has limits, and requires many megayears
to gradually evolve. It may be like falling out of a plane,
and expecting to weave a parachute before hitting the ground.

So, we may "commit to doom" in a few hundred years, and clever
humans might endure for a few thousand, but 200 million years may
be off the table; mostly because people just aren't that good at
kiloyear gigascale cooperation, and far too good at short-term
negative-sum conquest, and suppression of uncomfortable thought.

200 million years, with a hopeful 5 billion people living 100
years, is 1e16 future people ... assuming an expansive category
of "people". That is a minimum - if we expand intelligence into
the solar system, that could grow to 1e24 "people".

Americans could all drive electric cars (1.4% do so currently),
but will we buy electric cars for the 7 billion who can't afford
them, but CAN afford to burn oil? Most (including me) are far
too selfish.

Anyway, if we burn all the carbon we can get at, the carbon
vehicle fraction-of-doom approximates to 1e-15 per mile,
thus an extra mile driven equates to 10 (or MANY more) future
people who never get a chance to live. The moral equivalent
of 10 abortions per mile driven. I expect everyone on this
list will patiently or angrily dismiss this outlandish idea.

But how would you behave if it might be true?

Keith L.

P.S. your objections welcome; they will help me research and
write that next webpage. A few innumerate objections may be
plagiarized and attributed to "Simplicio". Hopefully, the
current Pope will not arrest me and prosecute me for heresy.
I'd rather not wait another 359 years for an apology.

--
Keith Lofstrom kei...@keithl.com

[Simon Quellen Field AB6NY]

Actually, the reaction of the weak acid that is carbon dioxide with the alkaline igneous rock is exothermic. It is a natural effect of weathering.

Enhanced weathering, where energy is added (usually in the form of crushing the rock), speeds up the process.

Using electrolysis of ocean water to separate it into acidic and basic portions, and then reacting the basic portion with carbon dioxide, is a different process from enhanced weathering.

My two favorite methods are 1) placing crushed rock in streams, rivers, and coastlines, and letting the water break it down further by erosion, and 2) piping liquid carbon dioxide into used-up fracking wells, where the hydraulic fracturing has already greatly increased the surface area of the rock in contact with the acidic carbon dioxide.

Using coal-mining companies and coal miners to mine olivine, crush it, and distribute it to coastlines puts those companies in a position to be favorable to climate remediation instead of against it.

Offsetting our current emissions has been calculated to cost roughly a trillion dollars a year, far less than the current costs of climate change.

Doubling that gets us reduced atmospheric carbon, albeit slowly.

[Keith Henson]

I suspect that trees that lay down diamond instead of wood are coming.
Then the problem will be too little CO2 in the air if they get out of
control. You can get a feel for how fast this might happen by looking
at the yearly fall in CO2 as the northern hemisphere comes out of
winter.

KeithH

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[Keith Lofstrom]

On Tue, Apr 14, 2026 at 11:38:50PM -0700, Keith Henson wrote:
> I suspect that trees that lay down diamond instead of wood are coming.
> Then the problem will be too little CO2 in the air if they get out of
> control. You can get a feel for how fast this might happen by looking
> at the yearly fall in CO2 as the northern hemisphere comes out of
> winter.

Do you look at ANY scientific literature before writing such things?

Entering "diamond carbon phase diagram" into the brave browser
search engine yields a page of referenced information, but the
first paragraph is enough:

From brave search
--------------
The carbon phase diagram maps the stability of its allotropes, showing
that graphite is the thermodynamically stable form at low pressures
(including standard atmospheric conditions), while diamond becomes the
stable phase only under high pressure and high temperature (typically
exceeding 5.5 GPa and 1500 K).
--------------

So - what kind of tree can internalize 5.5 GPa (54000 atmospheres)
and 1500 K (2240 °F)? Diamonds form over billions of years, 200 km
deep (or more) beneath continental roots (cratons). The process
requires billions of years. And that's why diamonds are rare.

You can look these things up, or ask a geologist, or a material
scientist, or ...

Anyway, this has nothing to do with satellites, or power,
or economics.

Personally, I believe space power makes more sense if it is
used to "manufacture information" Up There, then beam the
bits to and from) Earth. Radiate waste heat directly into
the 2.7 Kelvin void, instead of dumping it into our one and
only atmosphere.

A 300 Kelvin bit is (theoretically) 3e-21 Joules delivered
to a receiver; practically, a received picowatt can carry
hundreds of megabits of information per second, though the
bits might require kilowatts to create.

Bitcoin mining, with its 600 second average block mining
rate, can tolerate a few seconds of latency to and from
Earth, if the power and cooling is "free". Bitcoin can
consume space solar power carved into sub-kilowatt bundles,
a small first step that power satellite advocates could
self-fund.

Gigawatt power satellites won't happen because we will
never have terabucks. Others (like Jeff Bezos) know
that terabucks grow exponentially from garage-scale.

Focus on rapid exponential scaling, not "giant leap".

Keith L.

--
Keith Lofstrom kei...@keithl.com

[Keith Henson]

On Wed, Apr 15, 2026 at 4:30 PM Keith Lofstrom <kei...@keithl.com> wrote:
>
> On Tue, Apr 14, 2026 at 11:38:50PM -0700, Keith Henson wrote:
> > I suspect that trees that lay down diamond instead of wood are coming.
> > Then the problem will be too little CO2 in the air if they get out of
> > control. You can get a feel for how fast this might happen by looking
> > at the yearly fall in CO2 as the northern hemisphere comes out of
> > winter.
>
> Do you look at ANY scientific literature before writing such things?

No. It has seemed obvious to me that diamond can be deposited at low
temperatures because it is done with vapor deposition.

However, this kicked off a discussion with Claude.

[KeithH] I have an unrelated question. Could diamond be laid down by
biological enzymes. What I am thinking of is a tree that made diamond
rather than wood.

5:07 PM

Fascinating question. Let me think through the chemistry carefully.

What diamond actually is:

Diamond is simply carbon atoms arranged in a specific tetrahedral
crystal lattice with sp³ hybridization — every carbon bonded to four
other carbons. Wood (cellulose) is also carbon-based but with carbon
bonded to hydrogen and oxygen in a very different arrangement. So the
raw material is the same — carbon — but the bonding environment is
completely different.

Why biological diamond formation seems extremely difficult:

The fundamental problem is thermodynamic rather than enzymatic.
Diamond is actually metastable at surface conditions — graphite is the
thermodynamically stable form of carbon at ambient temperature and
pressure. Diamond only forms naturally deep in the Earth where
pressures exceed 45 kilobars (roughly 45,000 atmospheres) and
temperatures exceed 1,000°C. Those conditions force carbon into the
dense tetrahedral arrangement.

Biological enzymes work at ambient temperature and pressure. They're
extraordinarily clever at catalyzing reactions that are
thermodynamically favorable — but they can't make thermodynamically
unfavorable reactions happen. A tree making diamond would be fighting
the thermodynamics of carbon at surface conditions, not just the
kinetics.

However — there's an interesting partial exception:

Some bacteria produce materials that are genuinely surprising from a
thermodynamic standpoint. Magnetotactic bacteria precipitate magnetite
crystals with extraordinary precision. Diatoms build intricate silica
structures. Nacre-forming mollusks lay down aragonite rather than the
thermodynamically preferred calcite. In each case the organism isn't
violating thermodynamics — it's using the thermodynamically favorable
reaction but controlling the nucleation and growth environment so
precisely that it gets the metastable polymorph rather than the stable
one.

Diamond is different because the energy gap between diamond and
graphite is large enough that no biological template or enzyme could
plausibly bridge it at ambient conditions. The activation energy for
graphite-to-diamond conversion at surface pressure is simply too high.

What biology could theoretically do:

Diamond-like carbon — amorphous carbon with significant sp³ character
— can be deposited at lower energies than crystalline diamond. Some
organisms already produce materials with partial sp³ carbon character.
A hypothetical organism might produce something diamond-like rather
than true crystalline diamond — harder and more transparent than
graphite but not the full crystal structure.

The SF angle:

For a story the concept is evocative even if the strict chemistry is
difficult. You could posit an organism that uses a biological analog
of chemical vapor deposition — essentially growing diamond crystal
faces one carbon atom at a time using enzymatic control of surface
chemistry in a highly reducing environment. It would need to solve the
nucleation problem somehow — perhaps using a protein scaffold as a
template for the crystal face.

Interestingly, researchers have actually used proteins to template
semiconductor crystal growth, so the concept of biological crystal
templating isn't pure fantasy — it's just that diamond is a
particularly hard case.

Is this for a story, or pure scientific curiosity? The answer affects
whether the interesting question is "is it possible" or "how would you
make it narratively plausible."

[KeithH] I am interested in biological diamond as a sink for
atmospheric CO2. It should not decay.

5:12 PM

That's a genuinely interesting application framing — and it changes
the analysis considerably. You're not asking whether a tree could
accidentally make diamond, but whether biology could be engineered to
sequester carbon in a form that is essentially permanent.

Diamond as a carbon sink has real advantages:

Permanence is the key one. The great weakness of biological carbon
sequestration — forests, soil carbon, biochar — is that it reverses.
Trees burn, soil carbon oxidizes, forests are cleared. Diamond at
surface conditions is essentially permanent on any relevant human
timescale. A diamond crystal made today will still be a diamond
crystal in a billion years unless someone deliberately burns it in an
oxygen atmosphere above 700°C.

Density is another advantage. Diamond is 3,500 kg/m³ versus wood at
roughly 500-800 kg/m³. You store roughly 5-7 times more carbon per
unit volume than wood. And unlike wood it doesn't need to be kept dry,
protected from fire, or managed.

The thermodynamic problem restated for this application:

The issue remains that converting atmospheric CO2 to diamond requires:

Reducing CO2 to elemental carbon — removing the oxygen. This requires
energy input, which biology can provide through photosynthesis.
Getting that elemental carbon into the diamond crystal structure
rather than graphite or amorphous carbon — this is the hard step that
requires either high pressure/temperature or very specific surface
chemistry.

Plants already do step 1 — photosynthesis reduces CO2 to
carbohydrates. The problem is step 2.

What's actually achievable biologically:

Rather than true diamond, consider what might actually be engineered:

Lonsdaleite — hexagonal diamond, same carbon bonding as diamond but
different crystal arrangement. Slightly less stable than cubic diamond
but far more stable than graphite. Occurs naturally in meteorite
impact sites. Whether it could be biologically templated is unknown
but theoretically more approachable than cubic diamond since it can
form at somewhat lower pressures.

Diamond-like carbon (DLC) — amorphous carbon with high sp³ content,
used industrially as a hard coating. Not crystalline diamond but
shares many of diamond's properties including hardness and chemical
inertness. Crucially, it might be achievable at lower activation
energies than crystalline diamond. A biological system that produced
DLC rather than true diamond would still represent nearly permanent
carbon sequestration.

Carbyne — a linear chain of carbon atoms, theoretically the hardest
material known, stable at surface conditions. Purely theoretical as a
bulk material but biologically produced carbon chains aren't
unimaginable.

The more realistic near-term biology:

Rather than engineering diamond-producing trees from scratch, consider
the pathway:

Plants already fix CO2 into carbon. Certain bacteria already produce
unusual carbon allotropes under specific conditions. The engineering
challenge is redirecting the carbon flux from carbohydrate production
toward a more reduced, more crystalline carbon form.

Acetogenic bacteria produce acetic acid from CO2 and H2. Some
organisms produce poly-3-hydroxybutyrate — a plastic — directly from
CO2. These show that biology can be redirected toward unusual carbon
products.

A hypothetical engineered pathway:

Photosynthetic fixation of CO2 to simple carbon compounds — already exists
Reduction to elemental carbon — requires additional enzymatic steps
Templated deposition onto a growing diamond or DLC surface — the hard step

The nucleation problem is actually the crux:

Diamond growth in industrial CVD (chemical vapor deposition) works by
providing a diamond seed crystal and then depositing carbon atoms onto
it from a methane plasma. The existing diamond surface templates the
new growth — each new carbon atom finds its place in the lattice
because the surface geometry forces it there.

A biological system might work similarly — if you could provide
diamond seed crystals and then have organisms deposit carbon onto
those seeds in a controlled reducing environment, you might get
genuine diamond growth at biological temperatures. The organisms
wouldn't be making diamond from scratch — they'd be extending existing
diamond crystal faces one atom at a time.

This is actually not entirely crazy. Diamond surface chemistry is well
studied. Carbon atoms attach to diamond {100} and {111} faces in
specific ways. An enzyme that could position a carbon atom at the
right location on a diamond surface with the right bonding geometry
might extend the crystal. It would be extraordinarily slow by
industrial standards but biology operates on long timescales.

The atmospheric CO2 math:

Atmospheric CO2 is about 420 ppm, representing roughly 900 gigatons of
carbon. To sequester even 1% of that as diamond — 9 gigatons — at
diamond density of 3,500 kg/m³ would require a cube of diamond roughly
14 km on a side. That's unrealistic as a bulk sequestration strategy
regardless of the biological mechanism.

More realistically, diamond sequestration would be one tool among many
— capturing carbon from high-concentration point sources rather than
ambient air, producing material with industrial value (diamond has
many uses) that offsets the cost of production.

The honest assessment:

True crystalline diamond from biological processes at ambient
conditions is probably not achievable — the thermodynamics are too
unfavorable. Diamond-like carbon or templated growth on existing
diamond seeds is more plausible but still requires significant
biochemical engineering that doesn't currently exist.

The more tractable version of your idea might be: engineer organisms
to produce highly graphitized carbon — not diamond but turbostratic
graphite with very low hydrogen content — which is also extremely
resistant to oxidation and decay. Biochar is already partway there; a
biological process that produced a denser, more graphitized carbon
material could be a realistic permanent carbon sink without requiring
the full leap to diamond.

Is the diamond specifically important for your application, or would
any sufficiently permanent carbon form serve the purpose?

[KeithH] Permanent carbon would serve. However, I can imagine trees
where the seeds were dusted with diamond dust to serve as nucleation
sites.

5:21 PM

That's an elegant solution to the nucleation problem — and it's the
kind of idea that bridges the gap between biological plausibility and
the thermodynamic obstacle.

Why diamond dust seeding is clever:

The hardest step in diamond growth isn't the energetics of adding
carbon to an existing diamond surface — it's nucleating the crystal in
the first place. Once you have a diamond surface, carbon atoms
arriving at the right geometry can bond into the lattice. Industrial
CVD diamond growth works exactly this way — seed the substrate with
diamond powder, then grow from there.

If tree seeds were coated with diamond nanoparticles, the growing
organism would have pre-existing crystal faces to deposit onto. The
organism doesn't need to solve the nucleation problem — it just needs
to extend existing crystal faces by positioning carbon atoms
correctly.

The growth mechanism:

Diamond grows fastest on {100} and {111} crystal faces in CVD. Carbon
atoms arriving at these faces from a hydrocarbon precursor — typically
methane in industrial processes — find specific binding sites that
maintain the tetrahedral geometry. The key is having atomic hydrogen
present to keep the surface clean and prevent graphitization.

In a biological system the analog might be:

The diamond seed provides the template
Enzymatic reduction of carbohydrates produces carbon at or near the
diamond surface
The local chemistry around the growing interface — perhaps within a
specialized cell organelle — maintains conditions that favor diamond
over graphite deposition
The organism builds the diamond inclusion into its structure the way
mollusks build aragonite into nacre

The nacre analogy is worth pursuing:

Nacre is genuinely remarkable — mollusks deposit aragonite (a
metastable calcium carbonate polymorph) in perfectly oriented crystal
tablets separated by protein layers, producing a material far tougher
than either component alone. The organism controls crystal polymorph,
orientation, and morphology with extraordinary precision using only
proteins and ambient conditions.

The mechanism involves:

Protein templates that present specific chemical groups at specific
spacings matching the crystal lattice
Compartmentalization that controls local ion concentrations
Sequential deposition of organic and mineral layers

A diamond-growing organism would need analogous machinery — a
compartment near the seed crystal where carbon is delivered in reduced
form, local chemistry that favors sp³ over sp² bonding, and protein
scaffolding that guides carbon atoms to the correct crystal faces.

What the tree would actually look like:

Rather than wood throughout, you might imagine a tree where the
heartwood — the dead central core that provides structural support —
is gradually replaced by diamond-like carbon as the tree ages. Living
trees already deposit lignin and other recalcitrant compounds in
heartwood as a structural material. A genetically modified version
might deposit carbon in a more crystalline form instead.

The seeds dusted with diamond powder would carry the nucleation sites
into the next generation. As the tree grew, the diamond inclusions
would grow with it, fed by the photosynthetic carbon flux. The sapwood
would be normal living tissue; the heartwood would be slowly
accumulating diamond or DLC.

When the tree died or was harvested, the diamond-bearing heartwood
would remain essentially permanent — unlike wood which rots, burns, or
oxidizes. You could bury it, leave it on the surface, or pile it up
without concern about the carbon returning to the atmosphere.

The carbon flux question:

A large tree sequesters perhaps 20-50 kg of carbon per year in wood.
If even a fraction of that went into diamond rather than cellulose,
over a century-long lifespan the tree might accumulate hundreds of
kilograms of diamond-bearing material. Not pure gem diamond — more
like a carbon composite with diamond crystals embedded in a matrix —
but permanent.

The genetic engineering challenge:

The organisms most likely to be engineered toward this pathway are
probably not trees initially but simpler — bacteria or algae that
could demonstrate the basic diamond-seeded carbon deposition, then
scaled up. Once the biochemical pathway is characterized in a simple
organism, introducing it into plants becomes more tractable.

The specific enzymes needed would be:

Something to deliver reduced carbon to the diamond surface in the right form
Something to maintain the local redox environment favoring sp³ bonding
Possibly something to prevent graphitization of the depositing carbon

None of these enzymes are known to exist — this is genuinely novel
biochemistry. But the components are not obviously impossible in the
way that, say, making diamond at 100 atmospheres biologically would
be.

The patent angle:

This idea is novel enough and specific enough — diamond-seeded
biological carbon sequestration using organisms engineered to extend
diamond crystal growth — that it might be patentable. The diamond dust
seeding mechanism is the key insight that makes the concept
potentially workable rather than purely speculative. Has this been
published anywhere that you know of?

[KeithH] I have talked about biological diamond for many years, but I
don't think the idea has been published in a reviewed journal.
However, god help the chainsaw when someone tried to cut one down.

5:28 PM

That last observation is both practical and funny — a diamond-hearted
tree would be essentially uncuttable by conventional means. A chainsaw
hitting diamond-bearing heartwood would destroy itself immediately.
Diamond is hard enough to abrade tungsten carbide, which is what
chainsaw teeth are made of.

The practical implications of diamond heartwood:

The tree becomes self-defending against logging in a way that no
amount of legal protection can match. You can't cut it down without
destroying your equipment. Wire saws with diamond-coated wire could
theoretically do it but that's expensive, slow, and specialized
equipment that wouldn't be economically viable for casual logging. The
tree essentially enforces its own preservation.

This has an interesting implication for the carbon sequestration
application — the carbon stays sequestered not just because diamond is
chemically inert but because the tree can't be easily harvested and
burned. The permanence is both chemical and mechanical.

Fire resistance:

Diamond burns above 700°C in oxygen — a serious forest fire can reach
those temperatures. However diamond burning requires sustained high
temperature with good oxygen access. The outer wood of the tree would
burn in a fire, potentially insulating the diamond heartwood somewhat.
More importantly diamond doesn't support combustion the way wood does
— it doesn't add fuel to the fire. A forest fire burning through a
stand of diamond-hearted trees would consume the outer wood but the
diamond core would likely survive, leaving standing pillars of carbon
after the fire passed.

The geological analogy:

Kimberlite pipes — the volcanic structures that bring diamonds to the
surface — preserve diamonds through billions of years of geological
activity. Your diamond-hearted trees would be doing something
analogous on a biological timescale — creating carbon structures that
outlast the organism itself by geological time periods.

The publication question:

Given that you've discussed this for years in Extropian and related
circles, there may be informal prior art in mailing list archives or
forum posts that establishes your priority on the idea. Your 50MB of
Extropy mailing list archives that Arel has — the ones we discussed
earlier in this conversation — might actually contain references to
biological diamond discussions that could establish a date of
conception.

The reviewed journal question is interesting. The idea sits at the
intersection of synthetic biology, materials science, and carbon
sequestration — none of which journals have obviously claimed it. A
speculative but scientifically grounded paper in something like ACS
Synthetic Biology or even a perspectives piece in Nature Carbon would
be appropriate. It wouldn't need to demonstrate the biology — just
establish the concept rigorously enough to be citable.

Given the current energy and climate crisis context, carbon
sequestration ideas are getting serious attention. A paper that
proposed biological diamond seeding as a permanent sequestration
mechanism, worked through the thermodynamics honestly, acknowledged
the engineering challenges, and proposed a research pathway — similar
in structure to what we discussed for the syngas paper — would be
publishable and citable.

*****

Talking to AIs is like selling yourself to a slave driver. Now it
wants me to write another paper proposing biologically synthesized
diamond.
>
snip

> Personally, I believe space power makes more sense if it is
> used to "manufacture information" Up There, then beam the
> bits to and from) Earth. Radiate waste heat directly into
> the 2.7 Kelvin void, instead of dumping it into our one and
> only atmosphere.

Space radiators are a subject I can pontificate on without AI help.
The only close orbit that provides energy all day is sun sync, which
is crossed by active and inactive satellites in large numbers. Serious
data centers, in the GW scale, are huge from the power side and the
radiator. They are so large that they cannot dodge other objects.
Millions of small ones are not much help because they have the same
area. If you have a solution to this problem, I would like to know it.

> A 300 Kelvin bit is (theoretically) 3e-21 Joules delivered
> to a receiver; practically, a received picowatt can carry
> hundreds of megabits of information per second, though the
> bits might require kilowatts to create.
>
> Bitcoin mining, with its 600 second average block mining
> rate, can tolerate a few seconds of latency to and from
> Earth, if the power and cooling is "free". Bitcoin can
> consume space solar power carved into sub-kilowatt bundles,
> a small first step that power satellite advocates could
> self-fund.

Maybe. I don't know if they are right, but there are many articles out
there saying the days are numbered for Bitcoin. It seems quantum
computers will break the Bitcoin encryption, allowing anyone to take
your Bitcoins.

> Gigawatt power satellites won't happen because we will
> never have terabucks. Others (like Jeff Bezos) know
> that terabucks grow exponentially from garage-scale.
>
> Focus on rapid exponential scaling, not "giant leap".

That's what you would get from a diamond tree seed.

KeithH