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New stainless steel can survive conditions for hydrogen production in seawater

sciencedaily.com

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Re: New stainless steel can survive conditions for hydrogen production in seawater

#131

Post by Animats »

whizzter wrote: post #15
londons_explore wrote: post #11

Earlier quoted context omitted.

I don't think the efficiency or longevity of electrolysis equipment is the limiting factor... The limiting factor is that natural gas is very cheap and cracking it to make blue hydrogen is really easy at scale, and gives off CO2 which is useful for injection into wells to increase production. That sets a price ceiling of hydrogen. At the other end of the scale, there are batteries to store 'free' electricity and rese…

There's one case, rural areas often have abundant energy sources (hydro, wind,etc) but few consumers, in Northern Sweden f.ex. a lot is produced but there's a lot of losses in transporting the energy south. Now, yes, as long as natural gas is cheap(inbetween US or Soviet wars) it'll probably be the core for hydrogen, however batteries won't help much in the north since the transmission rather than usage is the cap ev…

China has this in a big way. The big energy sources are mostly in northwest China, and the big loads are in the southeast. That's why China leads in million-volt DC power transmission.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#132

Post by Gibbon1 »

londons_explore wrote: post #11
pjc50 wrote: post #5

So apart from the clickbait, the reason why this is interesting is because it's a limiter for the often cited idea of clean green hydrogen from electrolyis. The current use of titanium and precious metals is, obviously, really expensive, so it's uneconomical to build something that only runs on "spare" electricity.

I don't think the efficiency or longevity of electrolysis equipment is the limiting factor... The limiting factor is that natural gas is very cheap and cracking it to make blue hydrogen is really easy at scale, and gives off CO2 which is useful for injection into wells to increase production. That sets a price ceiling of hydrogen. At the other end of the scale, there are batteries to store 'free' electricity and rese…

One interesting use is hydrogen to feed microbes. The driver potentially is solar panels produce 30-100 times more energy an acre than corn. So what if you use solar to produce hydrogen to feed microbes which then produce various feed stocks using nitrogen and CO2 from the air.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#133

Post by oh_my_goodness »

IAmBroom wrote: post #107
KennyBlanken wrote: post #85

Earlier quoted context omitted.

How strange utility grids are spending on BSS and not hydrogen infrastructure. How strange utility grids are spending on HVDC transmission and not hydrogen infrastructure. HN commenters should ring up their local electrical grid operators and set them straight /s Also, if you have extremely low cost of electricity: you build manufacturing nearby that needs massive amounts of energy, like metal refineries. Or you subs…

So, do you have a materials science degree, or are you claiming you know more than the trained experts already tackling these issues IRL? I'm tired of Internet Experts(tm) announcing how dumb the specialists are for not seeing the Obvious Facts.

The pervious comment includes '/s' and appears to be a complaint about internet 'experts'.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#134

Post by cduzz »

SoftTalker wrote: post #123
dec0dedab0de wrote: post #89

Earlier quoted context omitted.

I think the best argument for hydrogen is for automobiles. Existing cars can be converted to use it, doesn't spray pollution all over the city, and can be refilled quickly unlike a battery.

Can existing cars be converted? Yes for CNG/methane or LPG/propane but not sure I've heard of Hydrogen conversions. Wikipedia says conversion to Hydrogen requires: ... hardened valves and valve seats, stronger connecting rods, non-platinum tipped spark plugs, a higher voltage ignition coil, fuel injectors designed for a gas instead of a liquid, larger crankshaft damper, stronger head gasket material, modified (for su…

Hydrogen is no good for cars because it sneaks into the metal and ruins it (hydrogen embrittlement). Your car is mostly metal, especially the part that stores the fuel and the part that makes it go boom.

You can probably make electricity directly from H2, and you can probably make special pressure vessels that'll store that H2 (though even then it'll have a 7 year "inspect thoroughly" and a 15 year "throw it out regardless" lifespan.)

H2 is a silly fuel unless you're making rockets. Or if you're trying to distract people.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#135

Post by nyeah »

pfdietz wrote: post #122
nyeah wrote: post #113

Earlier quoted context omitted.

The link points out that formaldehyde is one product of the methane-Cl reactions. Not sure we're better off with the formaldehyde (and its own further reaction products) than with the methane. They're not exactly talking about destroying methane. The methane is turning into chlorinated organic compounds.

Formaldehyde is also the product of the natural oxidation of methane by OH radicals. No, the methane isn't being turned into chlorinated organic compounds. The reaction mechanism is CH4 + Cl --> CH3 + HCl. (Caveat: I don't think the side reaction CH4 + Cl --> CH3Cl + H occurs, but I need to confirm.) The chlorine ends up as hydrochloric acid, which washes out in rain. If you object to the acidity, note that the elect…

The methyl radicals will also react directly with the chlorine.

If anyone else is reading along, please do not attempt to use chlorine gas to "destroy" methane in air that anybody's going to be breathing. That would be very dangerous.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#136

Post by coryrc »

IAmBroom wrote: post #103
BiteCode_dev wrote: post #41

Earlier quoted context omitted.

With solar sometimes producing a lot of energy when you don't need it or can't store it, having a cheap hardware to produce hydrogen from it is quite nice. Natural gaz may be cheap, but you can't beat free. For this setup, the price of the hardware was a limiting factor.

As always, the question is not "do this for solar, or not?". The question is, "Is this a valuable & efficient way to store energy?". It has to compete with pumped weight (usually water), pumped heat (salt, water, or underground), electric batteries, and so on. So, as always, it's complicated.

I would say your question needs to be expanded to "Is this a valuable & efficient way to store energy which can be scaled to any location?". The pumped options aren't. Batteries are cost-effective for time-of-day shifting, but not long term. Electrolysis and gas tank storage can be built in any climate, any terrain. Then benefit from economies of scale while the others are stuck in niches.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#137

Post by coryrc »

bell-cot wrote: post #52
londons_explore wrote: post #11

Earlier quoted context omitted.

I don't think the efficiency or longevity of electrolysis equipment is the limiting factor... The limiting factor is that natural gas is very cheap and cracking it to make blue hydrogen is really easy at scale, and gives off CO2 which is useful for injection into wells to increase production. That sets a price ceiling of hydrogen. At the other end of the scale, there are batteries to store 'free' electricity and rese…

> The limiting factor is that natural gas is very cheap and cracking it to ... Another, or perhaps related, limiting factor is just how difficult hydrogen is to handle safely - compared to natural gas, batteries, or other alternatives - https://en.wikipedia.org/wiki/Hydrogen_safety . And it does not take many surprise explosions & fires to give a technology a bad rep. Especially when people feel there are obviously-s…

Hydrogen is used as feedstock for many industrial processes, but also converting it to methanol should be the way to go for seasonal storage, but getting cost-effective hydrogen is the harder step.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#138

Post by toast0 »

pfdietz wrote: post #128
toast0 wrote: post #71

Earlier quoted context omitted.

Yep... Anyone who looked at how CNG cars went in the US and was like yep, let's do that but with a gas that's harder to transport and store and has no existing network, had to know it wouldn't work out very well. CNG fleet vehicles work out for many fleets; especially those that have vehicle depots where fueling happens. I haven't looked into detail for the hydrogen cars, but I wonder if they made the same kinds of d…

In its defense, hydrogen cars would use fuel cells, not the IC engine of CNG cars. So there's at least a theoretical case that could be made for them. In practice it didn't work well at all. The case for BEVs becomes even more clear when you look at complexity. BEVs are just simpler, even simpler than today's IC engine cars. IC engines have become baroque and expensive. The tooling needed to make these engines has be…

> In its defense, hydrogen cars would use fuel cells, not the IC engine of CNG cars.

Looking at a CNG car and thinking the reason they didn't get adopted is ICE and not gaseous fuel is pretty silly. Fuel cells are cool, but they don't solve the problem of tank expiration, and hydrogen storage is harder than CNG storage.

ICE may be complex, but most of the complexity comes from emissions controls / efficiency mandates. CNG "solves" emissions. You could burn hydrogen, and you'd really solve carbon emissions, if your hydrogen wasn't just coming from natural gas anyway. You'd probably need DEF, because high combustion temperatures with air intake from the atmosphere is going to generate NOx. Might not be as efficient as fuel cell vehicle, but it really doesn't matter when the problem is the fuel.

BEVs are clearly going to win as ICE is pretty close to fully optimized and batteries are still getting better. Although, if you could make a fuel cell vehicle based on a STP liquid that is energy dense and reasonably non-corrosive, it would have a chance.

Re: New stainless steel can survive conditions for hydrogen production in seawater

#139

Post by asa400 »

amluto wrote: post #126
asa400 wrote: post #54

Very interesting. Highly corrosion resistant "unconventional" steels have become somewhat popular in cutlery, with steels like LC200N, H1/H2, and MagnaCut. LC200N and H1/H2 in particular can be left in body of water uncoated/unpainted and come back in a year and they'll be fine. Obviously that's a different setting than electrified seawater for hydrogen production, though. So much cool materials science happening!

I'm not at all convinced that the highly corrosion resistant knife/tool steels you mention are actually especially high on the corrosion resistance scale -- I think they may just be excellent for a tool steel . If you look at the knifesteelnerds article on H1 ( https://knifesteelnerds.com/2019/06/24/h1-steel-how-it-works... ), you'll find that it's an austentitic alloy (which is highly unusual for any sort of tool st…

Entirely possible! I'm definitely not an expert. I own a few of these (LC200N and Magnacut) and I can confirm they've held up well in my own use of getting wet/dirty/etc. vs. other tool steels I have. Where they stack up against non-tool steels or steels not commonly used in cutlery, I couldn't say.

That said, I have heard plenty of anecdotes confirming these properties from other folks. People losing a knife in a stream or field and then finding it the following year, etc.

> In any case, this new alloy is weird -- it seems like it specifically has excellent resistance to electrochemical corrosion when it is used as an anode, which is not what people usually use stainless steel for :)

100%. Probably almost no crossover into cutlery, but super cool regardless!

Re: New stainless steel can survive conditions for hydrogen production in seawater

#140

Post by pfdietz »

nyeah wrote: post #135
pfdietz wrote: post #122

Earlier quoted context omitted.

Formaldehyde is also the product of the natural oxidation of methane by OH radicals. No, the methane isn't being turned into chlorinated organic compounds. The reaction mechanism is CH4 + Cl --> CH3 + HCl. (Caveat: I don't think the side reaction CH4 + Cl --> CH3Cl + H occurs, but I need to confirm.) The chlorine ends up as hydrochloric acid, which washes out in rain. If you object to the acidity, note that the elect…

The methyl radicals will also react directly with the chlorine. If anyone else is reading along, please do not attempt to use chlorine gas to "destroy" methane in air that anybody's going to be breathing. That would be very dangerous.

I already addressed that point. The chlorine concentration is quite low, so the reactive methyl radicals will react with oxygen first. This is unlike the industrial synthesis of chlorinated derivatives of methane, where methane and chlorine are present at high concentration and oxygen is excluded.
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