Found: The 'holy grail of catalysis'– turning methane into methanol | Hacker News Reader

Found: The 'holy grail of catalysis'– turning methane into methanol

phys.org

341 pointspseudolus147 comments

I'm wondering if the last sentence from the abstract is more of a holy grail than the conversion of methane to methanol:

> ... The confinement of mono-iron hydroxyl sites in a porous matrix demonstrates a strategy for C–H bond activation in CH4 to drive the direct photosynthesis of CH3OH.

https://www.nature.com/articles/s41563-022-01279-1

Selective C-H bond activation (of which this paper is an example) is extremely difficult. It has been the focus of intense research for decades. Having a tunable catalysts system that performed this transformation would be a game-changer for the production of just of about every organic molecule. The authors just focused on methane as the hydrocarbon feedstock, so it's hard to know how general the process might be.

That doesn't sound very selective to me, considering that the CH bonds on methane are all theoretically equivalent. Could you expand on this idea?

Selective here means it adds a single OH (alcohol group) to methane and not two, there, four.

If you keep adding alcohols (otherwise known as oxidation), you would end up with CO2 and waters - the same as burning methane.

There is a massive property boon going from methane (gas) to methanol (liquid and easy to transport) and not further

Is adding an OH to CH4 energetically equivalent for each successive OH added? Or at least close enough for the difference not to matter?

The first oxidation step, from an alkane, like methane, to an alcohol, like methanol, is always the most difficult, i.e. the least likely to happen spontaneously.

The next oxidation steps, from an alcohol to an aldehyde (formaldehyde in this case), then to a carboxylic acid (formic acid in this case), then to carbon dioxide, are much easier to initiate.

So doing the oxidation only up to methanol, without losses into more oxidized compounds, is not likely to happen in the absence of a very selective catalyst, like in this case.

This makes sense, thank you for the in-depth answer!

I mean, if the claims hold up and _only_ work for this particular interaction, it will still be workd-changing. Methanol production underpins an embarrassingly large chunk of the modern world.

Paper: Direct photo-oxidation of methane to methanol over a mono-iron hydroxyl site by An, B., Li, Z., Wang, Z. et al. Published in Nature Materials in June 2022.

Publication page: https://www.nature.com/articles/s41563-022-01279-1

Digital Object Identifier: https://dx.doi.org/10.1038/s41563-022-01279-1

Apparently the technique works at close to standard temperature and pressure. Considering that the Sabatier process can be run off water and electricity, and desalination can be done with sunlight, we have all the puzzle pieces for converting seawater to methanol via solar power. The chemical byproduct is oxygen, itself very a very useful element though difficult to compress and store. Even if the byproduct O2 is released to the atmosphere this looks very promising.

I have a tangential question:

> "The process is 100% selective—meaning there is no undesirable by-product—comparable with methane monooxygenase, which is the enzyme in nature for this process."

It seems like it should be pretty easy to get any given enzyme mass-produced. What is the reason we're not just growing a bunch of methane monooxygenase and using it to convert methane?

> What is the reason we're not just growing a bunch of methane monooxygenase and using it to convert methane?

Probably the same as every other eco-friendly "get rich quick" scheme - the precursors are relentlessly unpleasant.

"So all you need to do is take your water and yeast and cellulose and put it into a container, then slowly add the uranobenzene and methylated lead, bubble some nickel carbonyl through it, and gently warm it up to 900°C..."

> "So all you need to do is take your water and yeast and cellulose and put it into a container, then slowly add the uranobenzene and methylated lead, bubble some nickel carbonyl through it, and gently warm it up to 900°C..."

It seems like a safe bet that production and use of an organic protein are best accomplished at temperature ranges normally maintained by whatever life forms naturally produce it.

Yeah, but this is what the workup always seems to read like :-)

That makes me think of this quote: "The heater was warmed to approximately 700C. The heater block glowed a dull red color, observable with room lights turned off. The ballast tank was filled to 300 torr with oxygen, and fluorine was added until the total pressure was 901 torr. . ."

from: https://www.science.org/content/blog-post/things-i-won-t-wor...

Even if you can mass-produce an enzyme and its necessary cofactors, it might not be easy to use it in an industrial setting. Some enzymes need a very particular environment to be stable (pH, temperature, salinity etc) or can be destroyed by side-reactions with other things in your tank. Some work only when bound to particular cellular components (e.g. the cell membrane). If they need energy to work then it's probably as ATP or NADPH, so you'd have to somehow supply that in your bioreactor. And of course you have to keep the whole tank sterile without damaging the enzyme.

These problems notably plague attempts to use the even-holier grail of nitrogenases, basically enzymes for synthesizing ammonia using N2 and water. The current standard process for industrially fixing nitrogen (the Haber-Bosch process) is energy-inefficient and uses about 1-2% of the world's total energy supply, mostly in the form of natural gas. So significantly reducing its energy usage would be a huge deal, but we haven't been able to do it, nor do we fully understand how nitrogenases even work.

You could also try to culture bacteria that do the whole process and maintain the enzymes for you. In the case of methanol synthesis though, even if you could do this you'd have to keep tes culture alive and working 24/7 at a remote industrial site. A flare stack is a lot simpler.

Are we likely to discover in (* x 10) years that an over saturation of O2 in the atmosphere is damaging in some kind of way, on a global scale? AFAIK breathing pure O (or O2? Not a chemist) isn't great for your health?

Medical oxygen tanks are over 85%.

That said everything would be more flammable.

Earth atmosphere is 21% O2 vs. 0.04% CO2 (up from ~0.03% CO2 prior to the human era.) Had all the gigatons of CO2 pumped into the atmosphere by human activities instead been O2, the effect would be negligible.

I would assume all the methanol produced this way is burned, taking the generated O2 from atmosphere to CO2.

Such a high level makes the terrifyingly large insects of the dinosaur era possible again

Here's a funny posting by the Terminix (bug spray) folks: https://www.terminix.com/blog/bug-facts/giant-prehistoric-bu...

It was actually before dinosaurs (Devonian and Cambrian Periods).

Probably not. Those large insects and other bugs could flourish because they didn't have effective competition. But increasing the oxygen level today isn't going to remove the ecosystem that prevents giant bugs from developing again.

Analogously, there's nothing about the atmosphere preventing giant ground sloths from existing, but they nevertheless can't exist because they're not compatible with humans.

They can't exist because they were exterminated in the comet strike of 10,818 BCE.

We don't know whether they would have coexisted with us. E.g., hippo population in Columbia is exploding. Megatherium sp. coexisted with hunter-gatherer humans for at least thousands of years.

Horses and camels can coexist with humans. They too were obliterated in the Americas by the comet strike.

But we anyway know people did hunt all of them, before that.

Atmospheric O2 is about 21%. CO2 is about 0.042% currently. It's 2 orders of magnitude difference, which is also why human activity can have a relatively large impact on CO2 concentration.

It is famously damaging, so much so that the event that led to the current high concentration of oxygen in the atmosphere is called the https://en.wikipedia.org/wiki/Oxygen_Catastrophe

Luckily, all the damage is already done, and our ecosystem is now well adapted to living in a bath of toxic gas.

I've always found it funny that oxygen, commonly pictured as the benevolent stuff of life, is actually such so dangerous biologically. It's really a change in perspective when you realize that the reason we can't survive for five minutes without it is that we're running countless tiny power plants that use volatile chemicals and constantly struggle to dispose of the toxic byproducts.

> I've always found it funny that oxygen, commonly pictured as the benevolent stuff of life, is actually such so dangerous biologically.

Water is similar.

The essence of life is turning things into other things; doing so is difficult and dangerous.

It's certainly not good for newborn babies - look up retinopathy of prematurity.

If you happen to have an article of converting sea water to methane, please post. My searches bring back methane dissolved in sea water and I'm curious where the carbon originates.

i think parent refers to the sabatier process, so the source of carbon is concentrated CO2 externally provided, not from seawater

You're converting Sea water to water (desalination) and then do electrolysis to get H2. You need to get CO2 from somewhere, you can use Direct Air Capture technology to get it from the air. Then you do this: https://en.wikipedia.org/wiki/Sabatier_reaction

This is all known technology, the problem is it's not very efficient. Ultimately the discussion in climate tech circles these days is usually that most people think you'll rarely ever do this. Whenever you can you'll use something more direct, like using Hydrogen directly as an energy carrier.

I love promoting the fact that RF (13.56 MHz) can directly electrolyze saltwater without electrodes (and without desalination). The process was discovered by an amateur radio technician and it was treated like pseudoscience because of breathless local news coverage that made it sound like it was a fuel source.

The YouTube video (“burning saltwater”) is a classic—but there still isn’t a proper study on the efficiency of the process. (The radio technician, John Kanzius, died of cancer).

https://youtu.be/Tf4gOS8aoFk

Edit: here is a scientific paper characterizing the process, which is pretty interesting. No calculation of efficiency, however. https://iopscience.iop.org/article/10.1088/0963-0252/22/1/01...

While he may not have gotten it more widely studied to evaluate the efficiency… did he publish more information about his process? Or did his methodology die with him?

Well, the method is shown in the video. Put a test tube of saltwater in front of an 13.56 MHz RF generator (radio antenna) and light ‘er up.

The paper I posted uses a focused beam of RF and more deliberate lab methodology. But with just 5 citations, I feel like there might be a missed opportunity.

Thanks for posting the paper! With anything RF related it can be a complete shot in the dark for anyone trying to reproduce the work without things like the frequency involved. I mean sure you could do some physics, pick a range of likely frequencies and scan around but then your at the mercy of how much power you can generate at tuneable frequencies and still relying on a bit of guesswork.

Even if it’s not efficient this is a great RF science demo so it’s good to spread the knowledge around. Thanks again for posting it.

It is unlikely that the exact value of the frequency has any importance.

They have used 13.56 MHz just because it is one of the frequencies for which it is easy to find high power industrial generators, which are used e.g. for induction heating.

Here’s a mildly optimistic future vision for large-scale hydrogen production:

* We build arrays of underwater resonating tubes (~ 17 m for 13.58 MHz) that optimize the RF process efficiency for generating hydrogen.

* Out in the open ocean, it’s powered by floating gigawatt solarpads.

* “Blossoms” of enormous mylar cells are continuously filled up with hydrogen.

* The mylar hydrogen cells are plucked and transported for further processing via drone zeppelins.

I like the cut of your jib.

Almost always, people think one new idea is as much as a new technology can take.

But I suspect people will prefer an underwater hose for transporting gases.

That is a fun discovery. But if it's producing the hydrogen and oxygen as a mixture, rather than two separate streams, as conventional electrolysis does, i'm not sure it's very useful.

It’s a good point. Electrolysis produces hydrogen at the cathode and oxygen at the anode, making separation easy. But columnar separation may also be efficient, as the hydrogen will easily float on the heavier oxygen. Not an expert, though.

Stoichiometric mixtures of hydrogen and oxygen are terrifying to work with. No thanks.

So, you separate it while it is still in the water.

How? What's your detailed suggestion for doing this.

"Membranes, my boy. Membranes!"

I just looked it up. Hydrogen is insoluble in water. Oxygen is quite soluble. So, circulating water through, the hydrogen will bubble out, while the oxygen will be carried away with the water. So, maybe no semipermeable membranes needed.

Worth a shot!

If you’re interested, I’d love to put together a technical sketch..

That would be very fun. I was going to email, but couldn't find you at Delft...

J.d.lomas at tudelft dot nl or dereklomas at gm ail

We have good membrane technology now. Lay it on the water surface, so only the H2 gets through.

Does oxygen dissolve more readily in water than does hydrogen? If so, you just keep a continuous flow of water so it doesn't saturate before it moves on, but the hydrogen still bubbles out.

I doubt you want the water hanging about, heating up, anyway.

I just looked it up. Solubility of hydrogen in water is negligible; but oxygen dissolves readily, although better in fresh than in seawater.

We already have all the ingredients to turn CO2+H2 into Methanol without an intermediate step turning it into Methane. There are already a few production plants, e.g. one by Carbon Recycling International.

It's not super efficient, but I am pretty sure you're not going to improve that by introducing an intermediate step.

> It's not super efficient, but I am pretty sure you're not going to improve that by introducing an intermediate step.

What's the foundation of that argument? An intermediate step that's achieved more efficiently and allows for a more efficient follow-up certainly can improve the efficiency of the overall process compared to one with less steps?

Most chemical synthesis steps produce side products. More steps means more %yield loss.

If it's possible you go from A->B at 80% efficiency. If we compare this with A->C then C->B need to be nearly twice as efficient to provide a better yield.

Remember these steps include losses due to non chemical reasons. You might have issues with your reactors or transferring the solution to a new reaction chamber might incur losses, etc.

In most complex organic synth situations, the full synthesis will be 8-20 steps or so, so we're talking about yields of %efficiency^x. Lowering X helps a ton.

In short, the alternate route needs to be really good to justify additional steps.

> I am pretty sure you're not going to improve that by introducing an intermediate step

Isn’t that the entire reasons catalysts are so valuable?

> It's not super efficient, but I am pretty sure you're not going to improve that by introducing an intermediate step.

Perhaps we could so with a llittle self-awareness?

To come here and simply state that all these PHDs develop a new process while you here rest in certainty that it is doomed to failure.

Without demonstrating any understanding of catalysts or anything beyong highschool chemistry. Without presenting any evidence or agument except 'extra step is bad'

I agree with your main point. But there are plenty of PHDs out there working on projects doomed for failure. That is actually one of the main reasons why my brother left organic chemistry research to become a software engineer (the cutthroat abuse of peer review was another). He was tired of all the people getting grants for projects doomed to fail. Sure some of them might accidentally stumbling onto something useful but he became tired of all research in this field into known dead ends.

God help anyone still getting grants for molecular electronics.

Traditional methane-to-methanol with carbon monoxide intermediate (based on steam reforming of natural gas):

CH4 + H2O → CO + H2

CO + 2 H2 → CH3OH

Direct reduction of CO2 to methanol without going through the methane, an already established technology (Fischer-Tropsch type chemistry):

CO2 + 3H2 → CH3OH + H2O

Methanol is a common feedstock for further chemical synthesis (such as making high-octane gasoline), so this is an option for fuels from direct air capture of carbon dioxide & electrolysis of water for hydrogen. Two methanol molecules are dehydrated to form dimethyl ether (CH3-O-CH3) as the initial step:

> "Methanol can be used to make a gasoline product. The process uses a special zeolite catalyst with pore size such that molecules up to C10 can get out of the catalyst. Larger molecules cannot be made with this process; therefore, a product is made with no carbon molecules greater than C10, which boils in the gasoline range. In this process, aromatics and branched-chain alkanes are made, which means the MTG process produces very high octane gasoline. Gasoline is the only product."

https://www.e-education.psu.edu/egee439/node/679

Besides being relatively easy to convert into a gasoline product, methanol is also a convenient fuel for fuel cells, for direct conversion with high efficiency into electrical energy.

When used for fuel cells, methanol does not have the storage problems of hydrogen, even if any equipment using methanol must be designed carefully, to avoid any leaks, which are dangerous because methanol is toxic and may cause blindness when ingested or absorbed through the skin.

Many don't know this but the most important thing to know about solar is that it is so far the only method of direct power generation that exists. Nuclear and various fossil fuels create heat that boils water to generate steam that turns a turbine to generate power. This adds cost and complexity that you can never get away from.

But solar by virtue of being direct avoids all of this so has a lower bound in cost that other methods of power generation will find it hard to compete with. Solar cells can be small so solar power is highly flexible. Plus it has no moving parts (other than sometimes solar cells are moved slowly to face the Sun as it moves through the sky) so it's upper bound for reliability is hard to beat.

I actually think solar is and will be the most important method of power generation in the coming centuries that will culminate in space-based solar power collectors.

So solar has the potential to be extraordinarily cheap, reliable and require no expensive infrastructure like power lines. Creating methanol is essentially a way of storing excess energy so this could be a real game-changer for developing nations that lack such infrastructure.

And even more so if the plants which produce solar products use solar power to offset. I wonder if they do that or not. I'm guessing it's not quiet that simple and distributors of the individual components vary in their methods.

Dyson sphere style

Solar power is intermittent. This make it far more expensive for practical, real world applications in large scale. Nuclear is the only thing that can realistically substitute fossil fuels. Solar is at best a niche due to the storage needs.

That is of course wholly false. It is why solar farms are going up all over the world, counted in thousands, while nukes are not.

Storage is cheap. We have myriad alternatives, according to local requirements. Efficiency used to be a worry, but solar has got so cheap, you just add panels to make up the difference.

> Storage is cheap.

And yet it's solar being built all over the world, not storage.

Storage is also being built.

But storage will lag in volume until intermittent sources like solar produces enough in any given region that there are significant periods of excess that aren't better to deal with by bringing other plants offline.

Right, it would be stupid to spend big on storage that cannot be charged up from renewables that exist. First you build enough renewables, to displace fossil fuel (and opex), then build storage when you cannot displace much fossil fuel, any more.

All this is easy for an operator to figure out, daily: add solar, fuel cost falls in exact proportion. When you have to turn off enough banks of panels enough of the time, you start building stuff to absorb that energy for later. But not until building more panels cuts your fuel cost less than building storage cuts your night-time fuel cost. (Wind input makes this calculation less deterministic.)

Exactly. There is some benefit to building some storage before then to reduce the need for peaker plants, and that is largely what happens today when storage gets built. E.g. Tesla's battery project in Australia a few years back for example.

Plus, if this catalysis system works, then excess electricity can power the process to convert methane into methanol as a chemical battery store.

That, combined with the ability to extract CO2 from the atmosphere and convert that into Methane would result in carbon neutral (or even negative, if any of the converted CO2 carbon breaks away from the O2 in the burning process as soot) any time power delivery.

Yes, you would be burning the methanol in an engine to turn a turbine but if the carbon for that process came from the atmosphere to begin with then who would be upset by that?

You could be using the excess power to actually sequester the carbon you extracted, and help fend off looming climate catastrophe.

But selling it let you pocket a few bucks, so the choice was obvious.

They should tax half the carbon you extract as if it were mined, unless you sequester it instead.

Burning hydrocarbons extracted from the atmosphere is carbon neutral assuming the electricity required for the conversion is solar/wind supplied.

Re-check your sources. A lot of pro-nuclear material out there is pure advertising from nuclear lobbies. Nuclear is a hugely expensive and high-maintenance way of generating energy. There's risks that don't show up in neat, averaged numbers, think Russia shelling a nuclear plant in 2022, that was on none of the yay-nuclear bingo cards.

GP poster is correct.

Instead of talking about propaganda, you should go check the sources you're telling other people to check.

South Korean energy does cost circles around subsidized wind and solar, and doesn't need ridiculous battery infrastructure.

Gen-3 PWR nuclear is, in reality, by far the cheapest form of power on Earth, and you'll never find any hard evidence from respectable sources saying otherwise. (Probably that's why you're poisoning the water with claims of lobbies and bingo cards.)

> There's risks that don't show up in neat, averaged numbers

No, there aren't. Nuclear has killed fewer people all of in history than any other form of power generation in its worst month. Almost no industry in human history, power generating or otherwise, has a human death safety record anywhere near as good as nuclear power's. (I can't think of a single specific counter-example. Can you?)

The worst nuclear disaster in history, Kyshtym, which most people have never even heard of, didn't kill as many people as a bad bus accident.

Please bring hard evidence with your next set of claims. No, I don't mean estimates from the 80s by non-doctors that never panned out.

> think Russia shelling a nuclear plant in 2022

Zero deaths. You wouldn't expect that from other forms of power plant being shelled.

Your examples work against you.

There's a reason why when we talk about deaths from other forms of power we talk about actual deaths, but when we talk about deaths from nuclear power, we talk about risk that hasn't occurred and what might maybe happen someday

If you look at the numbers, and say "yes, but in my imagination," then you're doing the wrong thing

You say "check your sources" but you haven't actually done that yourself, yet

You talk about "advertising from nuclear lobbies" but nuclear fans' sources tend to be the government

Well, hydro or wind power don't have their own heat engine (the planet of course does stuff with sunlight that ultimately moves the turbine blades, yes)

> Nuclear and various fossil fuels create heat that boils water to generate steam that turns a turbine to generate power. This adds cost and complexity that you can never get away from.

That part is almost negligible. A General Electric LM6000 turbine costs about $20 million and generates about 50 MW of electricity. That translates into $400 MM per GW.

Solar comes to about the same price, but it has a capacity factor of only 30%, vs 98% for the GE LM6000 turbine.

98% not counting periodic overhaul. Then, 80-90%.

But you have to add the cost of the heat source. When that is a nuke, cost balloons out of sight. Geothermal is better, but drilling is still expensive; that might come down if microwave drills work out.

But the cost of periodic steam turbine overhauls will be hard to bring down to match dusting off PV panels. Pressurized steam is just very corrosive stuff.

That is why the mirror-array solar projects all failed. Steering thousand of mirrors, keeping them clean, and then driving a steam turbine just cannot match a static array of PV panels. The technology might have a place for supplying process heat, but it will be hard to match PV-powered fuel synthesis for cost and convenience.

Here’s a study by the DoE that shows that the capital and operating cost of a steam turbine that generates 15MW is about $666 per kW.

That would scale to $0.7 BN for a 1 GW plant, which is negligible for a nuclear power plant.

The steam turbine is definitely not what keeps the nuclear power plants from being economical.

[1] https://www.energy.gov/sites/prod/files/2016/09/f33/CHP-Stea...

nuclear doesn't use cheap small turbines like that. the output is far too large and they're nowhere near efficient enough.

a 1gw plant is currently about $7.5 billion, most of which isn't hardware but cost of capital, so the price you're claiming is 10% of total, which is hardly "negligable." Typical US buildout is 71% cost of capital, 15% equipment, 12% construction, 2% permitting, so, the number you're claiming would represent half of the entire plant equipment cost, which isn't correct

nuclear plants typically use either two or three very different kinds of turbines, which are an order of magnitude different in price - msbs, lsbs, and maybe elsbs if the plant is big enough

EDF's entire nuclear turbine business - they're one of the largest on earth - is only valued at 1.1 billion, which at your price is ... less than two turbines

https://www.nasdaq.com/articles/edf-seeks-to-lower-price-of-...

I can't follow your argument. You seem to imply at the same time that my numbers are too small and too high. Which one is it?

In any case, here's a separate reference to corroborate my numbers. It's a study by EIA ( US Energy Information Administration) published in 2020 [1] where they compare the capital costs of different power plants.

One such power plant they consider is a nuclear plant with 2 AP1000 reactors with a total capacity of 2.2 GW. The conventional part of the power plant is listed at $1.4 BN (page 107), which comes at about $640 MM/GW, in line with the estimate from my previous comment. Their overall estimate for such a power plant is about $14 BN, which means the conventional part of the plant is about 10%.

Of course, in the case of Vogtle 3/4 (which uses 2 AP1000 reactors), the overall cost is estimated at about $25 BN, due to various cost overruns.

[1] https://www.eia.gov/analysis/studies/powerplants/capitalcost...

> I can't follow your argument. You seem to imply at the same time that my numbers are too small and too high. Which one is it?

The devices are too small and the numbers are too high. (These things can be looked up.)

You know, kind of like how if you build a $300k machine out of A100s, and then try to match it with 3090s, you end up spending $800k.

> The conventional part of the power plant is listed at $1.4 BN (page 107), which comes at about $640 MM/GW, in line with the estimate from my previous comment.

Sorry, no, your comment was about the turbines, and the document you're linking to is about *the entire plant*.

Please stop trying to google-fight your way through this. You can't learn with your finger in the air.

The issue with turbines is not their capital cost (which is on par with the still falling all-included cost of PV) but rather operating cost. Steam turbines need frequent, expensive overhauls because superheated steam under high pressure is very hard on everything inside.

Renewables suffer no opex of such scale. They age out and need to be replaced, on a time scale of decades, but will be much cheaper to replace, then, than they cost up front. Probably perovskites will be used to replace silicon.

Both their initial and their replacement cost is wildly higher than nuclear.

Comparisons without a null hypothesis are defunct by nature.

> 98% not counting periodic overhaul.

the reason for the null hypothesis is that if you had run one, you'd realize that solar has a 20 year periodic replacement, as compared to nuclear's 80 year periodic maintenance, so this argument (like all arguments) is against solar

> When that is a nuke, cost balloons out of sight.

Not when compared to literally any other power source

But if you hold it up in isolation, yeah, sure, it's expensive. Once every 50 years because of bad laws, you have to go in there and pay about a quarter what the plant was worth.

And it'd still be cheaper if you had to do it every ten years, plus more reliable, and it wouldn't waste all the copper and rare earths, and it wouldn't leave you with China as the new Middle East.

> But the cost of periodic steam turbine overhauls will be hard to bring down to match dusting off PV panels.

You don't dust PV panels off. That's daily cleaning.

Maintenance for PV panels is replacing them every 12-23 years depending on what brand you bought.

An honest discussion would really help.

> That is why the mirror-array solar projects all failed.

No it's not. Also, the mirror-array solar projects do better than the PV ones, if you take the time to look it up.

The reason the mirror-array solar projects failed is, like the PV projects, they bought into the myth of storage.

> but it will be hard to match PV-powered fuel synthesis for cost and convenience.

This is the only good reason to use PV, and it's because the end product that's desired is a chemical battery

Batteries are the only thing PV can fill, and gasoline is the only kind of battery anyone actually wants to buy

In the meantime, the idea of using PV for this is absolutely absurd. It's 1/5 the price to do it on nuclear, and you know, it turns out that people are sensitive to the price of gasoline.

If you do an actual comparison with actual numbers where all the solutions are checked for every claim, instead of just the one you want to make look a certain way, suddenly you realize why nobody's building this despite that all the parts are cheap and unregulated, and despite that the market demand is vast and well established.

If this was true, instead of posting about it, you should be building a proof of concept, then applying for a bank loan, so that you can get rich saving the planet.

Cheap off the shelf parts don't do world-saving things, in general, or else someone would have already done it. If you believe that you can do something the world's scientists and engineers are desperately struggling to do using stuff you can buy at WalMart, there's a very solid probability that you're missing some key pieces in the evaluation, and should look up one of the publicly available studies.

> Nuclear ... create heat that boils water to generate steam that turns a turbine to generate power.

One of my greatest disappointments as a kid was learning this. I'd thought nuclear power somehow got the power of the atom directly to a wire/grid.

Maybe RTGs [1] that are used on some spacecraft will reappoint you.

[1]: https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...

Love the comment and the use of the word “reappoint”. Never thought of the root of the word “disappoint” prior

Aneutronic nuclear fusion with direct energy conversion is the dream

https://en.wikipedia.org/wiki/Direct_energy_conversion

the kid in you wants to hear "it's basically a steamboat"

Now I hope this is the dystopia with nuclear paddle-wheel steamboats.

i mean. that's kind of what us nuclear submarines are, just, all jules verne-y

and without the action of a casino

These would also count as "direct" power generation, I think (how should it be defined?). None of them work at scale, yet.

https://en.wikipedia.org/wiki/Betavoltaic_device

https://en.wikipedia.org/wiki/Thermoelectric_generator

https://en.wikipedia.org/wiki/Thermophotovoltaic

https://en.wikipedia.org/wiki/Direct_energy_conversion

> reliable

This is not usually a word that one uses to describe something that works when it wants to, as opposed to things that work when you want them to

> Nuclear and various fossil fuels create heat that boils water to generate steam that turns a turbine to generate power. This adds cost and complexity that you can never get away from.

Back here in reality, nuclear is much cheaper than solar, once you ignore the subsidies and the US-specific legal overhead

More importantly, it's base load, meaning you don't need the batteries that are riotously more expensive than water boilers

> I actually think solar is and will be the most important method of power generation in the coming centuries

Wind and solar are older than the grid, and have never been able to contribute

Energiewende failed

Humanity has no realistic non-nuclear future, and people should be required to look at the economic numbers before discussing this

> that will culminate in space-based solar power collectors.

Found the person who grew up on SimCity

"Boiling water adds too much complexity so let's build an infrastructure in orbit"

> Creating methanol is essentially a way of storing excess energy

One of many. There are much better ones. We generally don't use methanol as a chemical battery, even though it can be, because we have such radically better options.

Methanol is almost solely consumed as a fuel or as an intermediate product from fuels

Besides, the great thing about base load is that when you have it, you don't need to store excess energy. You just create the amount you need

You're solving problems that don't need to exist, while calling the normal way "too complicated"

This is a pretty basic chemistry question, but I thought someone her might be able to give a simple explanation why it seems most of these amazing catalysts are always made from precious metals. Why is it that super expensive things like gold and silver and platinum are always the backbone of these catalysts?

The orbitals of the lowest elements on the periodic table are the largest in diameter and most flexible in bonding and rebonding.

Their ability to easily make relatively short lived bonds is the key.

These metals are often super poisonous for the same reason (heavy metal poisoning). They enter a biological system and effectively randomize a whole lot of bonds and molecules you want to be stable over decades.

By "lowest elements" do you mean elements with lowest atomic number (Hydrogen, Helium, Lithium, etc.), or closest to the bottom of a chart hanging on a wall (Rubinium, Strontium, Yttrium, etc.)?

It would seem to be the latter, given the reference to heavy metals (they probably mean noble metals more likely)

No. They are contrasting the elements operated on, mostly light elements, with heavier ones used in catalysts that are also toxic, for reasons.

Not really. It’s because of the D- orbital configuration of the coinage metal family.

I guess if it was possible to make it with common dust, they would have been discovered for long with random trial alchemist experiments, and so wouldn't look so amazingly uncommon?

Those metals are very stable and usually don’t take part in reactions as reactants, and are usually catalysts, as you already mentioned. Meaning, they let the reactants form intermediates that wouldn’t form without the catalyst. Eg by donating an electron that is given back when the reaction is complete.

If the catalyst were not stable, it would become a reactant and be consumed quickly.

Because they are themselves less likely to react permanently with any of the intermediary products or the feedstock. Think of them as 'machinery that doesn't wear out quickly' which would make them a consumable.

Precious metal tend to not bond for very long time. Making them rather useful as catalyst. On other had my guess is that this tendency also leads them to be rare in uppermost crust of Earth as they didn't bound with other materials, but mostly sink to lower, them also being rather dense on virtue of being where they are in periodic table. This rarity is what actually makes them expensive.

Here's a BBC report from... 4 years ago.

What has changed since then?

https://youtu.be/MexeR2VozMA

Improvements in efficiency and a change of the MOF catalyst.

Here's a better casual news link for the 2017 Lehigh University | Cardiff University work: https://thebrownandwhite.com/2017/10/11/lehigh-cardiff-unive...

A brief description of some of the applications of methanol from the Methanol Institute:

https://www.methanol.org/applications/

Interesting. I've got a background mental process looking for results on large volume industrial applications of photochemistry. The reason is that these could provide a market for power beaming from space via lasers (and use of lasers might make power beaming practical on a much smaller scale than with microwaves, due to the much shorter wavelength). The laser light could be used directly in the photochemical process without having to convert it back to electricity.

This is very nice chemistry, but as usual for these articles that showcase some breakthrough, there is no net energy accounting of the whole system. How much energy+money is used to make and use the catalyst versus how much is generated, what the break-even point would be, and is it remotely realistic or not for that point to be achieved.

Things I'm wondering:

At scale, could it be cheaper to convert methane to methanol for export, compared to exporting LNG?

Would it be difficult to convert chemical plants using methane feedstock to use methanol instead?

I'm assuming natural gas power plants wouldn't be convertible, but coal plants maybe would. What would that cost?

I think the majority of gas, at least in EU, is burned in residential heating units. Even assuming new burners that would work with methanol, I don't think you could send that through the existing gas pipes.

Is methanol even safe to burn?

What do you mean “safe”?

methanol + oxygen = water + CO2 + energy

This is high school chemistry…

The exact physics of the reaction impact burner design and how much work is needed to adapt a burner designed for one fuel to another (sometimes impossible even if you're replacing gas with gas).

Methanol is highly toxic; it is important to consider how we can make pumping it into people's homes as safe as possible.

Is methanol more toxic than gasoline?

Not sure if you meant something else but just in case, "the majority of gas, at least in EU, is burned in residential heating units" means natural gas i.e. methane, not petrol/gasoline

> I'm assuming natural gas power plants wouldn't be convertible

Nah, gas turbines are relatively flexible wrt fuel. Might need different injector nozzles.

They will mostly all be converted to burn ammonia before long.

a lifetime ago my physics prof quipped that fluid dynamics was so difficult to model injector nozzles were still bit of a trial and error, wonder if this is still the case with all the modern computing prowess and perhaps better understanding of fluid dynamics?

Methanol has a surprisingly low energy density. Here's a comparison with other fuels:

  - methanol:  20 MJ/kg
  - ethanol:   30 MJ/kg
  - crude oil: 42 MJ/kg
  - gasoline:  46 MJ/kg
  - methane:   54 MJ/kg

Currently the world ships about 400 million tons of LNG per year. To get the same quantity of energy, you'd need to ship 1 billion tons of methanol.

It does not automatically follow that methanol would be a bad alternative to LNG. Even if you need 2.5 methanol tankers for each LNG carrier, overall their cost could be lower, because they are simpler machines. The transportation cost would be probably higher, but transportation is not a huge component of the price of energy (it's just maybe 2%). The storage at the receiving site would be much simplified. Maybe the loading and unloading would be faster, even with the 2.5x multiplicative disadvantage.

But overall this 2.5 lower energy density is still a very unpleasant aspect of the methanol as an alternative fuel.

But it's safer to transport and does not require pressurization and it boils off much less.

This has happened in WEst Virginia. They have stranded natural gas, that is no easy pipeline access, so it is available at a discount. China uses enormous amounts of methanol, so they funded a plant to convert the methane to methanol for export to China.

Catalysts requiring light typically never make it into industrial processes. They tend to be very slow because they can only act on a surface rather than through the whole volume of material to be reacted.

Methane is supposed to be abundant on some planets and moons. Would there be enough light available to turn it into rocket fuel for trips back?

Not sure . the amount of sunlight you get decreases with radius^3 and already at mars it gets quite low. Any planet beyond is probably not going to cut it.

r^2, right? It'd be ~r^3 if vacuum represented significant path loss to light at the kinds of ranges we're talking about.

Right. But solar insolation at Mars is, indeed, low, just by the r^2 phenomenon. 40%, IIRC.

But you should be able to use perovskite panels and not worry about them getting wet, oxidized, or hot. Those can operate at up to 40% efficiency, gaining back the difference. And, they are very light. You ought to be able to keep dust off electrostatically.

Not that anybody will ever live on Mars, or need methane there.

Methane is already a viable rocket fuel. I don’t think it would make sense to convert to methanol first.

Methanol is actually one of the oldest liquid rocket fuels, dating to WW2.

https://en.wikipedia.org/wiki/C-Stoff

I don't think it's a very good rocket fuel (it's already partly oxidized, for a start). Clark's Ignition says Nazi wartime shortages were the reason for its addition to C-Stoff -- I'll quote page 13:

- "But peroxide is not only a monopropellant, it's also a pretty good oxidizer. And Walter worked out a fuel for it that he called "C-Stoff." (The peroxide itself was called "T-Stoff.") Hydrazine hydrate, N2H4-H2O ignited spontaneously when it came in contact with peroxide (Walter was probably the first propellant man to discover such a phenomenon) and C-Stoff consisted of 30 percent hydrazine hydrate, 57 of methanol, and 13 of water, plus thirty milligrams per liter of copper as potassium cuprocyanide, to act as an ignition and combustion catalyst. The reason for the methanol and the water was the fact that hydrazine hydrate was hard to come by — so hard, in fact, that by the end of the war its percentage in C-Stoff was down to fifteen."

Now we need another step to efficiently convert methanol to ethanol.

That would truly be a "holy grail" - from methane gas to alchool :)

Can't wait to sell flatulence vodka to hipsters

Here you go:

https://www.sciencedirect.com/science/article/pii/S245192941...

This would be useful for dairy farmers. Addition revenue for cow farts and greenhouse gas reduction.

How do you collect the methane though ?

I was wrong, the methane capture that exists is methane from the manure.

https://www.npr.org/transcripts/1077235578

Found this for cows' burps

https://www.zelp.co/

Most of the current collection is from manure.

Methane is lighter than oxygen and azote, so you should be able to collect some at the highest point of an air-tight roof of a cow shed. Not sure how much that would represent compared to manure.

Ranchers interested in extra revenue would put up solar panels in pasture. Cows keep the weeds down.

Future generations will think solar farms in the desert were a dumb idea. But it is easy to get investor money for that, because investors don't know what a poor choice of placement that is.

Solar panels in the desert keep away NIMBYs (sometimes) and are good for the local wildlife by providing shade, especially if you can put them over what water sources there are.

You do much, much better floating them on reservoirs.

Los Angeles has not floated them in its reservoir filled with black plastic balls yet for probably NIMBYish reasons, but it will keep coming up every year.

so if we fly crop dusters full of catalyst over ranches, can we turn cow farts into disinfectant?

Pedantically: The methane from cattle comes in burps

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