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Hi, has anyone else heard of this. A friend of mine has said that he's heard about some research being done in Scotland (?) using some sort of aluminium derivative that when you put it into water it boils and releases the hydrogen. Don't know how true this is.
 

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There is a simple chemical reaction that produces hydrogen, I think from memory its aluminum and sodium hydroxide.

What is the intended purpose/product of the reaction?
 

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As above - aluminium is a rather reactive metal, but forms an oxide layer almost immediately making it resistant to acid attack.

Sodium hydroxide removes this layer and allows the aluminium to release hydrogen leaving behind sodium aluminate.

2 Al + 2 NaOH + 2 H2O → 2 NaAlO2 + 3 H2

As a primary source of hydrogen to fuel vehicles it is utterly retarded as the energy required to make aluminium metal, retrieve and compress/store the hydrogen in the first place, is mahooooosively greater than that released from the hydrogen being put through a fuel cell.

I don't know if the reaction is used industrially to create aluminates so there may be some hydrogen released that would otherwise be of limited value as a secondary product.

Tell yer mate to give up already on hydrogen - J.Clarkson is a buffoon and his science is and always has been weak.
 

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Oh my.

This serendipitous discovery, announced in July, has the potential to reinvigorate the hydrogen fuel industry.
How can you reinvigorate something that was never invigorated in the first place ?

aluminium that could react with water in a sustainable way would be able to produce hydrogen on demand.

This would make hydrogen fuel cells much easier to use since there would be no need to pressurise and transport hydrogen gas for use. Instead, simple, stable tanks of water and pieces of aluminium would be all you'd need.
Only requiring you to carry around a large quantity of bulky aluminium metal (inserted into the "fuel tank" how exactly ? Like shovelling coal into a boiler perhaps ?) which will be consumed by the reaction, as well as a source of water, all to produce a gas and leave lots of waste product behind. Awesome! :p

This would make hydrogen fuel cells much easier to use since there would be no need to pressurise and transport hydrogen gas for use. Instead, simple, stable tanks of water and pieces of aluminium would be all you'd need.
I know what my car is missing right now - large tanks of water! I can't wait. :D

The new material is stable and remains ready for use indefinitely. The starting material for the alloy is inexpensive scrap aluminium, which is fairly plentiful and cheap.
Except that the new aluminium that was smelted which only later became scrap aluminium used massive amounts of electricity in the smelting process - probably more than the energy it will release in hydrogen! :rolleyes: Aluminium is more expensive than steel precisely because the smelting process is so energy hungry.

While there might be scrap aluminium now, there won't be any available if all the cars in the world were hungrily consuming it... then you'd have to pay the full price of new smelted Aluminium. And what do you do with the leftover byproduct ? Empty it into a collection bin like emptying a used ashtray ? At least a "conventional" Hydrogen fuel cell car only had water vapour as its waste product...

Hydrogen gas has been hailed as a clean fuel for some time, but its widespread use has been hampered for practical reasons. It is bulky, demanding pressurisation, making it tough to transport and store.
Oh, and we forgot to mention that it's also been hampered due to the very high cost of the fuel cell to convert the hydrogen to electricity and the fact that the fuel cell has a limited life, poor efficiency, and uses expensive and rare catalyst materials...
 

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Ah yes, but you'd be able to toss your beer can into the ali tank, and in an emergency, to overcome range anxiety cut pieces of the vehicle bodywork off to feed the machine! That's if it doesn't consume the bodywork all by itself.
 

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Discussion Starter #8
I've heard a bit more. This uses nano somethings of aluminium and the aluminium nano thingies react with the water causing it to boil and give off hydrogen. Only happens in the lab though. It's news from August last year.
 

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Only requiring you to carry around a large quantity of bulky aluminium metal (inserted into the "fuel tank" how exactly ? Like shovelling coal into a boiler perhaps ?) which will be consumed by the reaction, as well as a source of water, all to produce a gas and leave lots of waste product behind. Awesome!
I think the idea is to transport the aluminium thingies and the water to a station in separate containers (I suppose the water could come from a tap) and combine them to make hydrogen on site. It's safer than transporting the hydrogen.

Apparently you can use the heat generated for central heating etc.
 

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I've heard a bit more. This uses nano somethings of aluminium and the aluminium nano thingies react with the water causing it to boil and give off hydrogen. Only happens in the lab though. It's news from August last year.
Unless it's a new process that uses an aluminium catalyst which is not expended in the process then it's a complete dead end.

Aluminium is an extremely energy intensive material to extract and would be a sustainable dead-end if it wasn't for the fact it is easily recyclable into new product.

Why waste electricity creating new aluminium for this process, or wasting scrap aluminium that has a high demand, when you could just create hydrogen through electrolysis?
 

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I think the idea is to transport the aluminium thingies and the water to a station in separate containers (I suppose the water could come from a tap) and combine them to make hydrogen on site. It's safer than transporting the hydrogen.
I read it as saying that it solved the problem of storing hydrogen in the car itself. Which is normally bulky, difficult and dangerous.

If it's only to generate hydrogen at a filling station why not just use an on site electrolyser instead ? Then your only raw material needed is water combined with electricity...
 

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It's potentially useful for those very special-case uses where cost is no object, energy efficiency is no object and some property of this system makes it more desirable than alternatives - it could be more silent than an ICE, works in the dark unlike solar cells, might be more energy-dense than batteries.

So maybe for some very small subset of military applications...

For EV use it's irrelevant.
 

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I reckon Lithium (density ~0.5g/cc) and water would make a better Hydrogen generator for such a nefarious outfit if energy density was the target.
 

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Discussion Starter #16
I read it as saying that it solved the problem of storing hydrogen in the car itself. Which is normally bulky, difficult and dangerous.

If it's only to generate hydrogen at a filling station why not just use an on site electrolyser instead ? Then your only raw material needed is water combined with electricity...
It's supposed to be more energy efficient as it needs no energy to work. As much as I have heard, you just drop these nano thingies into the water and a reaction takes place releasing heat and hydrogen (and oxygen?)
 

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There are numerous clips on youtube of idiots doing this reaction and setting fire to the hydrogen.

I think the breakthrough was that with their special new nano-aluminium they didn't need nasty chemicals (NaOH) to make the reaction occur.
 

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It's supposed to be more energy efficient as it needs no energy to work. As much as I have heard, you just drop these nano thingies into the water and a reaction takes place releasing heat and hydrogen (and oxygen?)
And how do they make the nano thingies? Dig them up out of the ground??
 

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Aluminium forms hydrogen in water. It is more reactive than hydrogen and strips the oxygen off it.

The thing is that Al is very reactive and really good at making oxides. So good that it forms a solid layer on its surface that passivates what's underneath to further reaction.

The 'secret' to making Al produce continuous hydrogen from reacting with water is to disrupt the formation of the passivation layer. You can do this in a few ways, such as making the particles of Al so small that there isn't enough thickness to make a layer, or to use something like mercury or gallium to make an amalgam. I am sure there will be plenty of new ways discovered once (or 'now') there is a reason to actually look for a way to do this. I'm sure there will be a 'simple' alloy found that prevents the passivation layer from forming, throw in a bit of tin into an Al alloy, something like that.
 
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