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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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unsure
By Chernobyl68 on 2/21/2008 2:58:12 PM , Rating: 5
Just some cons off the top of my head...

it takes a LOT of energy to refine bauxite into aluminum. While recycling of the used material will eventually become the norm for this process, it will require a HUGE investment in mining and refining initially. Transportation of the mass quantities of recycled material will require energy (how much hydrogen is produced from a 50,000 pound truckload of aluminum alloy?) Also, aluminum is a widely used building material (cans, jet airliners, etc) so there will be an impact on the world market of aluminum prices if this hits wide production. What impact will this have on the economy? I don't believe we want to fall into the same trap as we are with ethanol, competing with an industrial food crop (corn) for fuel.




RE: unsure
By KristopherKubicki (blog) on 2/21/2008 3:09:43 PM , Rating: 2
I would think though, we would transport hydrogen from the mine site, not transport aluminum to the hydrogen depot.

Either way, we'd still need a ton of energy to get this kick started.


RE: unsure
By Chernobyl68 on 2/21/2008 3:17:20 PM , Rating: 2
that's a good point, you can easily pipe hydrogen in a gas form I suppose, unless there's some technical problem with hydrogen transports that I'm unaware of...but I think their idea is to have the material at the gas station (for lack of a better term) and use piped water to make the hydrogen, which there's already an infrastructure for.
But, water is not plentiful everywhere. This won't be as popular in dry states like California, Arizona, New Mexico, Wyoming, etc. Many of these states are facing large water crisis' of their own. Using that water to make fuel rather than for consumption, industry, or agriculture has issues.
If this process could be adapted to be used with sea water that would be the "gold ring" in my book.


RE: unsure
By geddarkstorm on 2/21/2008 3:28:00 PM , Rating: 2
Sea water shouldn't be a problem, since it's water and aluminum that react. Though, there could always be other side reactions with salts and iodine in sea water they would have to test for. You can distill all that out of sea water, but that does cost a bit.

The beauty of using hydrogen too is that it just reacts with oxygen to form water all over again.


RE: unsure
By pauluskc on 2/21/2008 4:23:32 PM , Rating: 2
could be interesting.. my car ran out of gas - just piss in the tank. :)

drinking and driving makes a whole lot of new sense now... "officer, I was just preparing for running out of hydro later".

Silly. But funny visual.


RE: unsure
By Mitch101 on 2/21/2008 5:16:34 PM , Rating: 2
Im holding out for a Diet Coke and Mentos powered car personally.

I can enjoy a beverage of my favorite soft drink with the waste. Of course it would probably taste flat but you get used to it after a while.


RE: unsure
By pauluskc on 2/21/08, Rating: 0
RE: unsure
By Chernobyl68 on 2/21/2008 3:45:02 PM , Rating: 2
I think the amount of alloy you'd need to convert a reservoir or cooling pond would draw notice...see my analysis below. Either way, I doubt it would happen so fast that it would lead to a catastrophic meltdown of a nuclear electric plant. likewise any doomsday scenario of converting the ocean to gas. That's the idea behind using seawater instead of freshwater, sewater is so much more abundant.


RE: unsure
By geddarkstorm on 2/21/2008 3:51:21 PM , Rating: 2
Do you even begin to realize how much aluminum it would take to "boil away" (react with) even a small lake of water? To react with just 50 tons of water (45,359,237 grams, or 2,519,957.6 moles) you'd need about 50 tons of aluminum (since very 2 moles of aluminum react with 3 moles of water). Now, 50 tons of water is the amount an adult blue whale swallows in a single gulp--not much at all in the grand scheme of things. Consider it takes about 1000 tons of water to grow 1 ton of grain and you'll begin to see you'd need so much raw, refined aluminum to even begin to affect the amount of water in this world substantially that it's not even funny.

But then, you do realize that the hydrogen will (if not captured and put to work as in say a fuel cell) just react with oxygen to form water all over again? It's because hydrogen and oxygen have such a low free energy for forming water that you don't find raw hydrogen naturally occurring anywhere on the globe.

Also, reacting water in a bottle into hydrogen would make a nice loud "boom" with the bottle finally burst, but that's it. It wouldn't be enough to take out a plane.


RE: unsure
By Keeir on 2/21/2008 3:19:11 PM , Rating: 2
I think the other way.

The genius of this system is that you don't need to really transport Hydrogen. Just solids. Then, at any filling location just drop this into local water and poof hydrogen at some predetermined wieght.

Isn't storage of hydrogen one of the biggest challenges preventing the use of hydrogen? This neatly transfer the problem to storage of semi-reactive metals and water, both which we have solutions too....


RE: unsure
By pauluskc on 2/21/2008 3:37:34 PM , Rating: 2
why not just convert the oil pipelines to hydrogen pipelines? there's already a huge infrastructre in place to distribute gasoline that could be used similarly for hydrogen.

maybe.


RE: unsure
By Cattman on 2/21/2008 3:56:11 PM , Rating: 2
Because hydrogen leaks out of everything in gaseous state. It will actually leak out of a sealed gas bottle. The atoms are so small they permeate everything. A weld or joint that is liquid tight will probably not be hydrogen tight. Keeping it liquid would be a nightmare as well.


RE: unsure
By FITCamaro on 2/21/2008 4:26:51 PM , Rating: 1
I'm no chemist, but I don't think hydrogen can leak through solid metal. A joint yes. But if you put hydrogen in a sealed metal container, I don't see it getting out.

Regardless of the practicality of this, the real problem is getting the oil industries to embrace it. Because really, they're the ones who have to. The government isn't going to put down the cash to replace oil. It's not really their business to either. And the oil industry is really the only ones with the billions it'll cost to convert our gasoline base infrastructure to a hydrogen one.

Even if it does happen, then the only downside is that a car is going to go far fewer miles on a gasoline tank sized hydrogen fuel cell than it would go on the tank of gas since you have to use a lot more hydrogen to get the same bang as with gas.


RE: unsure
By SolarHydrogen on 2/21/2008 4:35:53 PM , Rating: 3
The issue with piping hydrogen is that it reacts with the metal, turning it brittle and susceptible to cracking.


RE: unsure
By geddarkstorm on 2/21/2008 4:45:04 PM , Rating: 2
It diffuses through some metals--especially steel--and can form pockets of hydrogen gas inside microscopic cavities. http://en.wikipedia.org/wiki/Hydrogen_embrittlemen...

I don't think it'd leak out at a rate of or in the sense of noticable loss of volume during piping. It'll just slowly destroy the pipes. It is a potential issue, which is why this reactive alloy technology is so cool and great.


RE: unsure
By Chernobyl68 on 2/21/2008 5:45:29 PM , Rating: 2
great article, thanks for the link.


RE: unsure
By drwho9437 on 2/21/2008 5:25:48 PM , Rating: 2
You are right you aren't. Hydrogen diffuses through "solids" at fairly low temperatures. The diffusion constant is just proportional to temperature, so at 300K it isn't what it is at say 600K but if you are going to have a lot of it, a lot of it will get out. Hydrogen is one of the hardest things to hold on to.


RE: unsure
By Oregonian2 on 2/21/2008 5:44:06 PM , Rating: 2
Aren't pipelines always being tested for microcracks (etc)? Seems like things would leak. But it's more than that, recall that for energy density the hydrogen has to be at really high pressures, something an oil pipeline wouldn't have been built for. Hydrogen also may be a bit more volatile than crude oil.


RE: unsure
By Keeir on 2/21/2008 6:19:22 PM , Rating: 2
Your also no Structural Analyst. Or Mechancal Engineer.

All gases create pressure vessal situations. To create the required density through put of Hydrogen, well, the gas will need to be at significant pressure. That pressure will put alot of strain (that is signiciantly different than Oil mass loading) on current pipe lengths and joints. The pumping mechanisms that work well for oil, they are not the most efficient for Hydrogen.

Then, the "last mile" that takes the hydrogen to "filling station"... the truck would need to be very strong indeed to withstand the PSI. To get current amount of energy storage as in a modern gastank type volume... that volume would be at 10,000 psi!. Aircraft typically operate at ~10 psi interal gage pressure for a point of reference.

Sorry folks, entire pipeline/gasoline infrastructure would need to be examined, reanalyzed, and potentially replaced to use it for Hydrogen transportation. Thats before Hydrogen Embrittlement and other issues.


RE: unsure
By FITCamaro on 2/22/2008 8:46:26 AM , Rating: 2
quote:
Your also no Structural Analyst. Or Mechancal Engineer.


I didn't claim to be. I'm a simple programmer. We leave those gases and stuff to the smart people.


RE: unsure
By Fritzr on 2/21/2008 9:25:56 PM , Rating: 3
My take on this one is shown in the photo ... You fill the car's tank with water, drop in a few briquettes and drive away. Remember the biggest headache in desingning an H2 powered car is how to store the fuel safely.

Filling Stations will sell briquettes and water instead of gasoline and diesel. Transportation of the alumina to the Filling Stations is much easier and safer than oil. Trains can carry bulk alumina, a good way to recycle the current fleet of coal trains :) Hopper trucks will deliver the final mile. Several designs for this kind of load exist. One is for potatos and simply scoops from the bottom of a hopper out the back gate. Another is the classic dump truck...Just back up to the briquette bin and upend the bed :)

Filling Stations will also buy back spent briquettes and send them back to the recycling center. The current recycler infrastructure will also welcome this new commodity that will need to be collected and returned for refining.

The H2 generator will need some refinement for use with 'dirty' water but that is a refinement that will be improved on in years to come.

In arid areas this will be a problem due to water shortage, but I can forsee "fuel" pipelines carrying water to "fueling depots"/tank farms and "fuel" trucks delivering water to Filling Stations just as is done today with petroleum fuels.


RE: unsure
By Chernobyl68 on 2/22/2008 4:29:58 PM , Rating: 2
I don't think you'll have a "spent briquette" left after you put this alloy on a tub of water. To react all of the aluminum you'd be breaking down the alloy atom by atom, so you'd likely be left with a slurry of alumina and other metals. This would then need to be resmelted to remove the metals, process the alumina back to aluminum, and then resmelt the alloy.


RE: unsure
By initialised on 2/22/2008 7:12:41 PM , Rating: 2
To get this started several small scale factories are set up to process recycled aluminium into pellets of reactant and to reprocess spent reactant. Ideal sites would be existing recycling facilities or, if it can be done small scale, existing filling stations.

These pellets are then loaded into small ~5-10kg canisters with an inlet for water and an outlet for hydrogen. The canisters could be made from a material with a sufficiently higher melting point than the fuel so that the canister could be used as a crucible in which the spent fuel is melted.

As you drive water is added to the canister to produce hydrogen. The hydrogen could either be used to top up a bank of capacitors and batteries via a fuel cell or burnt in an internal combustion process or both in a hybrid drive-train. Either way you would have a vehicle with a hydrogen fuel line supplied by the canisters output and a water tank whose size would be governed by the power-to-weight ratio of the vehicle. Since a canister would have a maximum output the minimum number of canister ports would be governed by the maximum hydrogen output required at peak load. The problem of filling up with water is much less of an issue as water is the output of both hydrogen combustion and fuel-cells. This 'waste' is simply recycled from the exhaust though occasional top ups would be necessary as it is unlikely that every water molecule successfully reacts to produce one alumina and two hydrogen atoms or that each hydrogen atom successfully binds to form a water molecule. However, it might be possible to minimise losses by using a liquid oxygen tank (hmmm... liquid oxygen direct injection internal combustion engine, could work underwater or in vacuum) but I digress.

When the reactant is depleted you simply replace the empty canister. Obviously any vehicle would have to have at least two of these replaceable fuel tanks. If peak output was more than a single can could provide then the minimum is three but range would be poor. Exceeding this max load +1 minimum would increase vehicle range. The +1 minimum exists because it is wasteful to dispense of a can before it is depleted and you cannot guarantee that you will run out of fuel at a filling station. In my twelve years on driving this has only happened to me once, I stopped at a diesel only pump in a petrol car and had to push it to the next one.

Used cans would be emptied, cleaned and refilled with pellets made from the waste product ideally in small automated micro-factory at filling stations.

As for the size of the tanks, well that would depend but keeping them under 10kg would help.

Once the infrastructure was in place there would be very little need for additional raw materials except to allow for surplus stock and cope with an expanding fleet and lost cans. Most of this could be obtained from recycled materials.

Whether this model is feasible depends on how far you can get in a typical car on this fuel, maybe it only scales up to portable electronics or down to heavy haulage. The inventors clearly believe it is commercially viable and I think this is an elegant and efficient way of doing it without the need for quarries or pipelines.


RE: unsure
By geddarkstorm on 2/21/2008 3:21:11 PM , Rating: 2
We have to mine aluminum anyways for cans, cars, planes, etc. It's also the most abundant metal in the earth's crust, so what metal would be better, and why would this process affect the economy that much? As with any new tech, you have to have to invest a lot to get it started, how is that different from anything else?

Alumina has the formula of Al2O3, so that for every 2 aluminum atoms, you'll make 3 molecules of hydrogen gas (H2). That being, 2 tons of aluminum should make 3 tons of hydrogen gas. You still need a relatively small amount of that inert catalyst in the alloy too, and that actually will be the most expensive part according to what they say.

Still, after 60 recycles, it comes out to 10 cents per kilowatt hour to pay for this technology, and recycling is almost 100% efficient? It's pretty dang good, better than most things, and thus it is commercially viable.


RE: unsure
By geddarkstorm on 2/21/2008 3:32:40 PM , Rating: 2
I goofed. Aluminum atomically weighs more than hydrogen, so you can't compare tons. Instead, 2 moles of aluminum should make 3 moles of hydrogen gas when using this process.


RE: unsure
By Chernobyl68 on 2/21/2008 3:40:46 PM , Rating: 2
yeah, I saw that...no big deal...:)


RE: unsure
By Chernobyl68 on 2/21/2008 3:38:31 PM , Rating: 2
assuming it is AL2O3, I'll take your word for that

2 Al + 3 H2O -> Al2O3 + 3 H2

Atomic Weights (rounded)
Al=27
H=1
O=16

2(27) + 3(18) = 102 + 3(2)

so it takes 54 tons of aluminum to make 6 tons of hydrogen gas (9 truckloads of aluminum to make 1 truckload of Hydrogen, roughly) and that's discounting the weight of the catalyst material.

seems its much cheaper to ship the gas than the new alloy.
and the AL2O3 is about twice the weight of the original allow by adding the oxygen. So you're creating roughly 18 truckloads of used material to be recycled, assuming a closed loop system where only the aluminum oxide from the fuel station is used to make the alloy down the line. If its isn't, then you add a third leg to the transport loop where the refined aluminum is taken somewhere to be made into the alloy. It seems far easier to ship the hydrogen by truck or pipe, on the surface. As I said, there may be some unknowns in piping hydrogen gas I'm unaware of.


RE: unsure
By SolarHydrogen on 2/21/2008 4:22:29 PM , Rating: 2
Hydrogen and our existing piping infrustructure do not mix well because the hydrogen reacts with metal, turning it brittle, and susceptible to cracking.


RE: unsure
By geddarkstorm on 2/21/2008 4:36:46 PM , Rating: 2
http://en.wikipedia.org/wiki/Alumina now you don't have to just take my word for it :).

Shipping the gas is actually rather difficult. You have to pressurize it into a liquid as H2's gas volume is 0.08988 g/L (the greatest there is, after all). Furthermore, H2 only goes into liquid form at around 2-4 kelvin (or -271 to -269 degrees C). The new honda fuel cell car has to pressurize to 5,000 psi for 171 liters I believe it was. On top of this, being that hydrogen is just two protons and two electrons, it can pass through most materials, including metal, which can lead to steel becoming brittle and failing.

Now, how much hydrogen do you actually need to produce a certain amount of power via a fuel cell? If the new honda really does use 171 liters for... was it 270 miles? Since liquid hydrogen is 0.070 kg/L, you have 13.2 kg of hydrogen in one of those cars and 1 metric ton = 1000 kg, so 1 ton of liquid H2 could fuel 75 of those cars for 270 miles (if I got the car's figures right). Doesn't seem like too much for 1 ton? If there's "About 450 million passenger cars travel the streets and roads of the world" as of 2001 ( http://hypertextbook.com/facts/2001/MarinaStasenko... ), you'd need 6,000,000 tons of H2 (or 54,000,000 ons of aluminum) to power them for 270 miles (if they were all that honda fuel cell car). That seems like a lot, except cars output 6.9 billion metric tons in of CO2 in 2004 ( http://64.233.167.104/search?q=cache:56cevd1CGJgJ:... ) into the air per year, so you can imagine how many tons of oil and gas we consume. So it seems roughly on par then. I don't have time to really finish the calculations (how much gas do we consume? How far does the average car drive per year? etc) as I have to go.

I think that puts things in perspective? Should check my work to make sure. But, it will certainly take a TON (haha) of aluminum to fuel such an economy--but shouldn't be anything more than what we have to spend on gas?, and thankfully aluminum is the most abundant metal in the crust. No one said making energy to fuel our life styles would be a cake walk ;)


RE: unsure
By Chernobyl68 on 2/21/2008 5:41:08 PM , Rating: 2
I estimate the average driver's personal car is about 14-15,000 miles a year. Possibly more than that for business ues.
assuing
13.2 kg = 270 miles, 15,000 a year, that's 733 kg per vehicle, per year. If you assume it takes 2 weeks to complete a circuit in the recycling loop (just a wild guess) you need 1/26 of that in kg to power that car, or about 28kg per car. multiply that by 450million, you get 12,692,307,692 kg or about 12.7 million metric tons of the worlds aluminum wrapped up in the loop., which according to world-aluminum,org, is a little more than the total amount scrap recycled in 1998.

http://www.world-aluminum.org/production/recycling...

so maybe I'm worrying for nothing, but its interesting to find out this information.


RE: unsure
By geddarkstorm on 2/21/2008 7:12:17 PM , Rating: 3
This is very interesting. At least to me as well.

Another way of looking at it is that if the 11.6 million tons of aluminum recycled in 1998 fulfilled 40% of the world's demand for aluminum, then that demand was 29 million tons for the year. Cars using 12.7 million tons would make the 1998 levels of world demand for aluminum increase by 70% to 41.7 million tons. Quite the jump in world demand, if this was done for all cars, instantly, overnight. Fortunately, the switch would obviously be gradual. However, one thing to consider is how much new aluminum would have to be added to the system per year, over what would be recycled (loss in conversion, increase in cars, how much we can expand our recycling abilities by)? That I can't begin to speculate on, but it would certainly be less and less with each year, so the picture only gets better as time goes on.

Gasoline has an average density of about 737.22 kg/m³ ( http://en.wikipedia.org/wiki/Gasoline ), or 0.737 kg/l, or 2.79 kg/gallon. "Therefore, in the United States, something like 400 million gallons (1.51 billion liters) of gasoline gets consumed every day" ( http://auto.howstuffworks.com/question417.htm ) which then comes to 1.1 million tons of gasoline used by the US alone per day!

So, on the one hand, based on 1998's standards, our aluminum infrastructure would be strained a bit by the demand if all the cars in the world switched to hydrogen produced by this aluminum alloy reagent right at this moment. Sure, we could put all our recycled amounts immediately into it, but that'd leave all the other sectors needing mined aluminum, meaning an increase of 40% in mining would have to be done. By 1998's standards. However, on the other hand, this isn't going to happen over night for all the cars of the world instantly.

But then, compared to how much gasoline we consume, the amount of aluminum it would take to run our cars on hydrogen via this method would be nothing. Nothing at all, in comparison. By the time this method became wide spread, our infrastructure would be more than capable of handling it (recycling is what would go up mostly, after the initial load of raw aluminum gradually leaked into the hydrogen production pool). Again, none of this would happen over night.

Our figures are probably pretty far off from reality, but they give a good perspective and picture. Just looking at that gasoline consumption.. always leaves me shaking my head in awe. Still, the biggest cost factor, especially initially, will be that 5 percent mixture of gallium, indium and tin. If we use 12.7 million tons of aluminum, that'd be 635,000 tons of that stuff (it can be nearly 100% recycled too, thankfully).

In any case, this has been very interesting to research. Thank you for getting me on this kick. Ultimately, we'll just have to see what comes in the future--if this stuff gets commercialized well, if it is presented to the market in a competitive way against gasoline (i.e. how it's priced and how that changes over time), and how the technology matures.


RE: unsure
By SoCalBoomer on 2/21/2008 6:49:49 PM , Rating: 2
And, as the aluminum in this system would not actually be consumed, but could be relatively easily recycled back into this catalyst, it's radically different than burning a limited resource.

The numbers you're giving seem right - but have you compared it to the amount of hydrocarbons we're presently using?


RE: unsure
By geddarkstorm on 2/21/2008 7:18:11 PM , Rating: 2
Very true, which I am unable to take into consideration in my calculations, unfortunately. But that is an extremely important point, and why this tech is so very cool. Reusable and renewable in almost every sense.

From the post I just made: "Therefore, in the United States, something like 400 million gallons (1.51 billion liters) of gasoline gets consumed every day" ( http://auto.howstuffworks.com/question417.htm ) which then comes to 1.1 million tons of gasoline used by the US alone per day. Quite a bit more than the aluminum we'd need, even if we couldn't recycle it!


RE: unsure
By Chernobyl68 on 2/21/2008 10:03:01 PM , Rating: 2
Well, gas and diesel aren't known for their density... :)


RE: unsure
By Chernobyl68 on 2/21/2008 10:11:56 PM , Rating: 2
well, since the end product is alumina (and not aluminum), technically I guess we shouldn't be calling it recycling, but resmelting. You're almost making bauxite over again.


RE: unsure
By Etsp on 2/21/2008 5:26:19 PM , Rating: 2
quote:
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.
Your very first con does not apply to this tech. Converting the alumina back to aluminum is cheaper than bauxite(at least, according to the article), however I'd like to see the comparison of those two conversions quantified, as that would really put this into perspective.


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 10¢/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?


RE: unsure
By Chernobyl68 on 2/21/2008 10:09:33 PM , Rating: 2
quote:
On average, around the world, it takes some 15.7 kWh of electricity to produce one kilogram of aluminium from alumina. Design and process improvements have progressively reduced this figure from about 21kWh in the 1950's.


http://www.world-aluminum.org/production/smelting/...


RE: unsure
By Etsp on 2/22/2008 9:31:30 AM , Rating: 2
Poking around on that same site I found this: http://www.world-aluminum.org/production/refining/...
it would appear that our current process of obtaining aluminum is to mine bauxite and convert that into alumina. So in essence, this new method of hydrogen production is eliminating the first step of a standard process, a step other methods require. That is a significant difference.


RE: unsure
By DWwolf on 2/22/2008 2:54:47 AM , Rating: 2
The only problem is that there isnt enough Indium to make this viable. We're already running out of Indium because of the rising demand for LCD monitors, which is used in small amounts for color filters.


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