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Jerry Woodall, a professor at Purdue University invented the new alloy production process, promising affordable, easy hydrogen.  (Source: Purdue University)

Pictures of the alloy in water, reacting to produce hydrogen, as evidenced by bubbling.  (Source: Purdue University)

The byproduct of the process is a recyclable mix of aluminum and gallium-indium-tin ores.  (Source: Purdue University)

Here a Purdue researcher uses the hydrogen produced by the process to power an internal combustion engine.  (Source: Purdue University)
While some hydrogen research focuses on simulating nature, a new metal reagent developed by Purdue University promises economic viability

Jerry Woodall, a distinguished professor of electrical and computer engineering at Purdue University, is firmly ground in the world of commercial production.  When he began researching ways to improve hydrogen production using aluminum reagents, his goal was simple -- if it wasn't commercially viable, it wasn't a success.

While recent researchers have reported significant breakthroughs in fields such as synthetic photosynthesis and microbial hydrogen production, these methods currently are too inefficient to currently be feasible as a non-subsidized fuel alternative.  While these methods are exciting in that they may one day lead to cleaner and more effective energy production, many agree that the time for hydrogen is now, and waiting for theoretical methods is simply impractical.

Fortunately Purdue's Woodall developed a more down to Earth method of hydrogen production that promises a feasible infrastructure and short term commercial viability.  Woodall states, "We now have an economically viable process for producing hydrogen on-demand for vehicles, electrical generating stations and other applications."

The key to the method is a new aluminum reagent, which Woodall invented.  The new reagent is composed of 95 percent aluminum and then a critical 5 percent mixture of gallium, indium and tin to improve its reactive character.  Previous similar alloys used far more gallium, which is very expensive.  By cutting down the gallium, Woodall greatly reduced the costs of hydrogen production.

When the new alloy is exposed to water, it reacts to create hydrogen gas and oxygen.  The oxygen then bonds to the aluminum to form aluminum oxide, also known as alumina.  It is cheaper to recycle alumina back to aluminum than it is to refine aluminum from bauxite ore, which is another element contributing to its efficiency.  Woodall illuminates, "After recycling both the aluminum oxide back to aluminum and the inert gallium-indium-tin alloy only 60 times, the cost of producing energy both as hydrogen and heat using the technology would be reduced to 10 cents per kilowatt hour, making it competitive with other energy technologies."

Control of the microscopic structure of the solid aluminum and the gallium-indium-tin alloy mixture is critical to the technology's success.   The mixture is a "two-phase" mixture, meaning that it features abrupt changes in composition between one constituent to another.  Woodall explains this challenge stating, "This is because the mixture tends to resist forming entirely as a homogeneous solid due to the different crystal structures of the elements in the alloy and the low   melting point of the gallium-indium-tin alloy.  I can form a one-phase melt of liquid aluminum and the gallium-indium-tin alloy by heating it. But when I cool it down, most of the gallium-indium-tin alloy is not homogeneously incorporated into the solid aluminum, but remains a separate phase of liquid.  The constituents separate into two phases just like ice and liquid water."

Researchers had two options -- fast cooling to leave separate alloys or slow cooling to yield a single solid alloy brick.  At first they tried fast cooling, which required a puddle of gallium-indium-tin to initiate the reaction.  However, when they turned to the slow-cooled alloy, they were impressed to discover that it reacted just as well, or better, eliminating the need for the liquid gallium-indium-tin alloy.  Woodall adds, "That was a fantastic discovery.  What used to be a curiosity is now a real alternative energy technology."

The Purdue team is currently completing work on developing a production method to produce briquettes of the alloy.  These briquettes could be dropped into a tank of water, producing pure hydrogen.  This would eliminate both the need for hydrogen storage and hydrogen transportation, two critical obstacles for the hydrogen industry. 

The gallium-indium-tin alloy in the process is inert and is able to be recovered with almost 100 percent efficiency.  Woodall says even the less efficient aluminum recycling produces much less carbon emissions than traditional fuel.  He states, "The aluminum oxide is recycled back into aluminum using the currently preferred industrial process called the Hall-Héroult process, which produces one-third as much carbon dioxide as combusting gasoline in an engine."

In order to fully realize the technology on a national scale for fuel use, alumina recycling infrastructure would need to be dramatically expanded.  Additionally, gallium-indium-tin recycling would need to be added.  This infrastructure would be expensive, but according to Woodall "the economic risk is large, but the potential payoff is also large."

Woodall won the 2001 National Medal of Technology, the highest award for technological achievement in the U.S.  Woodall his fellow researchers will present their findings on Feb. 26, 2008 at the Materials Innovations in an Emerging Hydrogen Economy conference in Cocoa Beach, Fla.  The alloy production process's primary patent title is owned by the Purdue Research Foundation.  Purdue has licensed the technology to an Indiana startup company, AlGalCo LLC., which Purdue hopes will be the first company to implement the technology commercially.

Purdue's solution is similar to the University of Leeds' new method of producing hydrogen from biofuel waste sludge, in that both solutions are economically feasible, but require the development of production infrastructures.  However the new method from Purdue can make hydrogen from a far more plentiful source -- pure water.


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RE: unsure
By Ajax9000 on 2/21/2008 10:03:06 PM , Rating: 2
IMNSHO there is either poor reporting being done here, or someone is hyping this work.

Firstly:
That new alloy is not a catalyst, it is a reagent. By definition catalysts do not get consumed in a chemical reaction (e.g. http://dictionary.reference.com/browse/catalyst ). This alloy gets totally consumed by the reaction.

Secondly:
What is the likely energy source for turning the alumina back into aluminium? Answer -- the usual suspects (used in current aluminium production): hydroelectricity, nuclear, fossil fuels. The synthetic photosynthesis development is a far more interesting development.

Thirdly (and following on from the above):
What is the advantage of this process compared to the current main sources of hydrogen (steam reformation of petrochemicals, electrolysis of water, etc.)? In particular, if alumina is being reprocessed using power from coal/petrochemical sources, how is this new process an improvement on steam reformation of petrochemicals?

I too would like to see come comparisons. I'd want to see energy budget and pollution comparisons with the other H2 production systems before accepting this as an advance forward (at the moment I'd call it an advance sideways).


RE: unsure
By geddarkstorm on 2/22/2008 1:44:01 AM , Rating: 2
Those are some very good points that have to be looked at in evaluating this potential technology.

The first point is easy to address at least. You are absolutely right it isn't a catalyst, however, the aluminum isn't "used up" into an unusable form, but simply must be reconverted. That is, nothing is lost physically (theoretically, but it'll never be 100% and some aluminum will slip from our notice along the way, even if just by human choice).

Now, the really important question that sums everything up is how much energy will we get back from the evolved hydrogen verses how much energy is used to turn alumina and raw ore (whatever ratios of both are needed to keep up our supplies) into aluminum? I haven't the foggiest in answering that. But that seems to me to be the real clincher in deciding if this is viable or not.

Third: This process is far more efficient than any yet. That is, as the inventor stated (though I don't know how he calculated it) after 60 recycles it'll cost us only 10 cents to produce a kilowatt hour of energy from this technology. That is very cost effective. It's like a fluorescent light bulb verses incandescent: the former is more expensive initially, but over time pays for itself and even saves you money if you have it around long enough. I think that's the crux of this technology, though I can't even start to evaluate if the inventor's claims are true. Still, it's the most viable and commercially competitive way of producing hydrogen yet (all other techs will take quite a while longer to reach the point were they may be commercially possible, let alone viable), or so it would appear.


RE: unsure
By geddarkstorm on 2/22/2008 12:29:28 PM , Rating: 2
Ok, here's something. Talking about theoretical maximums in energy production from hydrogen (notice, these values can never be reached because of inefficiencies in capturing and transferring energy, and heat loss): the energy produced by the formation of water is 400 kJ/mol. So, say we have 6 metric tons of hydrogen (from 54 tons of aluminum). That gives us 3,000,000 moles, so reacting all of that to water would give off 1,200,000,000 kJ of energy. Since Joules Per kilowatt-hour (kWh) = 3.6*10^6, we get 333,333 kilowatt-hours from this 1 ton of hydrogen.

Now Chernobyl68 pointed out "it takes some 15.7 kWh of electricity to produce one kilogram of aluminium from alumina". So to recycle 54 tons (54,000 kg) it would take 847,800 kilowatt hours. Therefore, in the end, we would lose 514,467 kilowatt hours . That's how much we'd have to put into this process to keep it going. Since the average cost of electricity is something like 10ยข/kWh in the U.S. ( http://www.eia.doe.gov/cneaf/electricity/epm/table... ), roughly anyways, that's $51,446.70 we'd be spending on energy to make 6 tons of hydrogen if all of the hydrogen's energy was being put right back into the grid and recaptured. A complete waste to do that.

Looking at it from another way for cars (and a more practical way, since the energy from the hydrogen isn't going back into the electrical grid if it's being used in a car), it costs $2,520 per 1 ton of aluminum ( http://www.commodityonline.com/commodities/metals/... ), or $136,080 to buy the 54 tons we used to make 6 tons of hydrogen. From earlier, I calculated 1 ton of hydrogen could fill 75 of the honda fuel cell cars. 6 tons would obviously fill 450 cars. This comes out to $302.40 per car to fill the 171 liter tank for a rang of 270 miles ! Not good at all. For a little over 20 bucks I could fill my Kia Rio and go about 350 miles if on the highway.

Looking at it this way, this tech doesn't seem good in the least as it is now (as aluminum is processed and costs now). So, you're right, as it stands it's a move sideways, or worst, backwards. (At least if my calculations are correct or anywhere near reality)


RE: unsure
By Grast on 2/22/2008 1:11:03 PM , Rating: 2
While, I have not had the time or inclanation to double check your numbers. Regardless of our personal opinions regarding global warming, we all agree that reliance on fossils fuels has to come to and end sometime.

I put forth the idea that energy needed to recycle the alumina would come from Nuclear sources rather than coal and/or gas. A nuclear infrustructor could make up the gap you calculations have pointed out.

I also submit that since refinement of alumina to aluminumum requires a large amount of contant electricity. This is the type of power which is acceled by nuclear power plants since demand is constant.

1. build nuclear plants
2. solve the issue of were alumina is recycled.
3. solve the issue of trace elements recycle.

this finally equals a realy economical solution for alternative to gasoline powered vehicles.

Later..


RE: unsure
By geddarkstorm on 2/22/2008 1:47:16 PM , Rating: 2
I agree with you fully. However, this is too far out of my league. Still, there should be a way to close the gaps on these figures. For instance, increasing aluminum production and expanding recycling systems should quickly drop the price of aluminum and potentially make the solution competitive. As things are right now, they are not set up for the sort of infrastructure and systems as would be needed by this technology--it is not optimized as gasoline as become from a century of use.

Our reliance on combustion engines does have to end, period. The question is how and when. It won't be easy because gas is so cheap, and it's so hard to move away from what we've already established. I've gone as far as I can in analyzing this, though it still is the best option for making hydrogen yet as far as I see and know; I leave it up to the future to decide.


RE: unsure
By Chernobyl68 on 2/22/2008 4:53:36 PM , Rating: 2
checking the numbers

$2500 per ton (I'm going to assume a 2000 lb ton)
so 9 x 2520 = about $22,700 for
for 1 ton of hydrogen, which is about 907kg H2.
at .07 kg/L
907 kg / .07 kg.L = just about 13,000 liters Liquid H2.
Filling a 171 Liter (about 45 US Gal) tank gives you
13,000 / 171 = 76 tanks (pretty close, but I've rounded)
$22,700 / 76 = $298 dollars a tank. not bad

Hydrogen is not a high "energy density" fuel like gasoline or diesel. Ethanol is better, but still not as good as a refined fuel like gasoline as far as energy density (this is why your mpg goes down while driving with ethanol fuel)

My belief is still, that the best course is to pursue all electric cars, or hybrids to help develop the bettery technology to better energy density.
We need a paradigm (sp?) shift in energy production, and hopefully will achieve commercial Fusion power in the next 50 years. Chemical energy production (largely fossil Fuels) will simply change the atmospheric content of our planet over the long term, and will have environmentally damaging effects at some point (when that point is is for better minds than mine).


RE: unsure
By initialised on 2/22/2008 10:03:23 PM , Rating: 2
Firstly:
Gallium, indium and tin are the catalyst (note [i]almost 100% recovered[/i]). Aluminium reacts but can be recovered easily as the article clearly states.

Secondly:
Once infrastructure is in place vehicle emissions (including water) are eliminated and fleet CO2 emissions drop by 66% (reprocessing makes 1/3 as much as petrol) or more while city air gets cleaner and 20th century smog becomes as quaint as London's legendary 'Pea-soup' smog. BTW cities are a great source of scrap aluminium.

Thirdly:
The advantages are that the H2 is stored as water in the vehicle (safety) and the energy required is stored as a solid which is intrinsically easier to transport, store, handle and safer than H2 in a pressurised container and it would exist as H2 for a very short time before becoming water again in the engine/fuel-cell so leakage would be minimised. Also steam reformation of petro-chemicals [i]requires[/i] fossil fuels.

I very much doubt that this method of producing H2 is useful for anything but producing H2 at the point of use as in transportations ever changing point of use.

The aluminium requirement (13 tonnes for the world fleet) is not going to happen in a year given that the average car has a lifespan of more than twelve years it would probably take more like 50, look at how long it's taken Diesel's more efficient and flexible engine to gain consumer acceptance.

The material [i]available[/i] for recycling is far greater than the material [i]collected[/i] and recycled. e.g. did you recycle your stock cooler when you upgraded to a better one? So discounts for the cans/fuel could be given to customers who supply scrap aluminium. If the filling stations incorporate small spent fuel recycling stations then there is minimal 'material transportation cost' and it would be in their economic interest to ensure this is done well as it would be their product quality that would encourage repeat purchases. Possibly more of a cottage industry than the globally fixed cartel we have now. e.g. the more your city recycles it's aluminium the less it has to buy in, the cheaper the fuel.

What really strikes me with this is it's simplicity and sustainability. I hope it has a place in the hydrogen economy.

1kg H2 ~ 20 miles
9kg Al + 450g Catalyst = 1kg H2
10kg can ~ 20 miles
200kg ~ 400 miles

Weight of water can be ignored as it will be relatively constant if recycled from the exhaust. Cars fuelled like this would get heavier by absorbing oxygen from the air.

http://corporate.honda.com/environment/fuel_cells....
Power = 134BHP ~ 100kW
Weight = 1.625t
PWR = 100/1625 = 60kW/t

How heavy is the H2 tank and battery in Honda's Fuel-Cell car, it seems very heavy (and slow) for it's output and size?


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