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Scientists at the University of Leeds have found a way to break biofuel byproduct sludge down into clean components

Biofuel is one form of alternative energy touted as a clean and renewable resource: a great alternative to petroleum fuel. But not everyone agrees. Hydrogen fuel is another popular alternative, as Honda recently demonstrated. Dr. Valerie Dupont and her team at the University of Leeds have come up with a way to make both more appealing -- and more importantly, cost effective.

The often unknown byproduct of biodiesel fuel production is glycerol, a sugar alcohol. While glycerol has many uses from food sweeteners to health care products to explosives, disposing of the low-value crude waste is becoming a problem. The process developed at Leeds turns this waste into clean hydrogen, water and carbon dioxide.

Dupont's separation process involves mixing glycerol with steam at a controlled pressure and temperature. This acts to separate the glycerol into base molecules of hydrogen, water and carbon dioxide, and leaves no other byproducts. The carbon dioxide is filtered out with special absorbent material, leaving the hydrogen and water.

Dupont explains, "Our process is a clean, renewable alternative to conventional methods. It produces something with high value from a low grade by-product for which there are few economical upgrading mechanisms. In addition, it’s a near ‘carbon-neutral’ process, since the CO2 generated is not derived from the use of fossil fuels."

The new process could be another step closer to a hydrogen economy. Creating an infrastructure for such a fuel system would be quite costly, but as more inexpensive methods to create the key element surface, the far-reaching idea is starting to look more plausible.


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Not really cleaner...
By dflynchimp on 12/1/2007 2:30:51 PM , Rating: 1
well lemme think...you need steam for this process...which requires boiling large amounts of water.

So we're going to have to burn natural gas or other conventional fuels...just like a regular powerplant, thereby spewing all this CO2 into the atmosphere...then use that energy to produce yet more CO2...I fail to how this is any cleaner for mother earth...




RE: Not really cleaner...
By Talcite on 12/1/2007 2:59:47 PM , Rating: 1
If you need to produce steam, there's several alternatives to burning fuel. You could heat it using electricity generated from solar or hydro or wind.

Aside from that point, even if they burned fuel to generate heat, it's much easier to capture at a central location. Have you heard about all the clean coal plants popping up all over the place? They have CO2 scrubbers installed along with various other scrubbers.

I'd say it's much better than having waste from biofuel build up. This is pretty much the epitome of recycling.


RE: Not really cleaner...
By Ringold on 12/1/2007 3:55:03 PM , Rating: 2
You didn't really help your cause with that one, I don't think.

So we're taking a food source, turning it in to a biofuel with questionable energy gains, and then taking the byproduct of this process and expending more energy on it to get this hydrogen. I don't really care about the CO2, since for me that's got nothing to do with if its viable or not.

You noted the heat could come from solar or wind, but those are both intermittent, and hydro or other sources have an opportunity cost in that they could be powering cities rather than this process, so that energy being fed in to the process isn't just free even if its renewable.

Perhaps its a good move in the right direction, but I guess we'll know if by itself it's enough if whoever provides the hydrogen for shuttle launches tries to license this to replace either their current natural gas or electrolysis source. If it were significantly cheaper I'm sure they wouldn't say no -- unless they have a cost-plus contract, in which case, I bet they use electrolysis.


RE: Not really cleaner...
By Talcite on 12/1/2007 5:06:14 PM , Rating: 2
Ahh I wasn't talking about the viability of biofuels. I'm not sure if they're the best option out there, I haven't done enough research on it. There's definitely a lot of issues with using food as fuel for cars and whatnot.

What I am sure of though, is that if biofuels every get adopted for one reason or another, we at least have a method of recycling the waste.

There's a LOT of use in industrial chemistry for hydrogen, not just shuttle launches. Ammonia fertilizer is simply nitrogen and hydrogen really. And the typical way of producing hydrogen right now is though methane formation, which evolves a lot of CO2 unfortunately. Electrolysis isn't nearly efficient enough. I would definitely keep an eye on this technology though.


RE: Not really cleaner...
By Ringold on 12/1/2007 6:39:19 PM , Rating: 2
Okay, yeah, no disagreement from me then.


RE: Not really cleaner...
By LogicallyGenius on 12/1/2007 11:57:44 PM , Rating: 2
Another load of crap from proponents of bio fuel farms (a threat to food security and world wide forests)

instead this is the real deal "Microbes churn out hydrogen at record rate"

http://www.biologynews.net/archives/2007/11/13/mic...


RE: Not really cleaner...
By LogicallyGenius on 12/2/2007 12:16:06 AM , Rating: 2
RE: Not really cleaner...
By StevoLincolnite on 12/2/2007 1:10:06 PM , Rating: 2
Or even create energy for it using Hydrogen, If it uses even half of the amount of hydrogen as it makes, its still worth it, is it not?


RE: Not really cleaner...
By masher2 (blog) on 12/2/2007 1:13:23 PM , Rating: 3
quote:
Have you heard about all the clean coal plants popping up all over the place? They have CO2 scrubbers installed along with various other scrubbers.
No. There are no coal plants at present that sequester CO2, nor does the technology yet exist to do so on a large-scale, cost-effective basis.


RE: Not really cleaner...
By JohnnyCNote on 12/1/2007 7:03:02 PM , Rating: 2
As I see it the answer couldn't be simpler or more obvious:

You use existing fuels to create a stockpile of H2, then you use the H2 as fuel to create more H2 and phase out the more polluting fuels.


RE: Not really cleaner...
By djc208 on 12/2/2007 8:57:33 AM , Rating: 2
That assumes the H2 generation process creates more hydrogen than it consumes, which would be very unlikely as you would in essence have a perpetual motion machine.

The steam however is really pretty easy, aside from the normal thermal sources (renewable and non) there's waste-to-energy plants, they reduce the wastes going into landfills and generate energy (the facility I work at gets most of it's steam from this method).

Or you could just take the output steam from a power plant. The steam coming out of a turbine would probably still have enough heat/pressure to be used for this task. A reboiler could boost it if not, otherwise that heat energy would normally just be dumped into a water source or the atmosphere to condense the water for re-use.


RE: Not really cleaner...
By JohnnyCNote on 12/2/2007 8:15:38 PM , Rating: 2
quote:
That assumes the H2 generation process creates more hydrogen than it consumes, which would be very unlikely as you would in essence have a perpetual motion machine.


Not really. You'd just produce enough to cover transportation as well as production needs, among whatever other needs that may arise. Being that it's the most prevalent element in the universe, there's no possibility of it running out. Production could be augmented with solar, hydro-electric, wind and other clean energy sources. You also suggested another source, steam.

Whatever the means, too many detractors are, deliberately or otherwise, ignoring the fact that the transformation to H2-based energy is a process that will take decades to achieve. They use this as a pretext to deny that any research at all should occur. Just as the gasoline-powered internal combustion engine did not come into mass use overnight, neither will engines powered by H2, but we have to start somewhere . . .


RE: Not really cleaner...
By dolcraith on 12/3/2007 3:30:17 AM , Rating: 2
quote:
in essence have a perpetual motion machine


Not really as its not like the steam is generating the hydrogen that is powering the production of steam that is ... etc etc. The reason its *not* perpetual is that if you don't keep putting in glycerol the process would stop. Perpetual would mean that you don't have to put any energy into it (ie the chemical energy in glycerol). But its moot unless the joules stored in the hydrogen produced > the joules to produce the steam. Honestly I believe finding a more biological process of producing hydrogen would be more beneficial.


How this CO2 is different?
By dsolecki on 12/1/2007 5:11:36 PM , Rating: 2
All of you seem to have missed an important point:
"How is the carbon dioxide (CO2) in this case of "LEED", any different than the CO2 that environmentalist are claiming as the top reason for the "global warming" hype?"

The way it is different is that the CO2 separated by this process comes from plant matter that recently captured it from the atmosphere. Thus making the process "carbon neutral".

The CO2 we all happily spew from our tailpipes comes from fossil fuels that have had that carbon trapped underground for millions of years.




RE: How this CO2 is different?
By TomZ on 12/1/2007 5:23:21 PM , Rating: 2
The net result seems the same to me.


RE: How this CO2 is different?
By mdogs444 on 12/1/2007 5:34:54 PM , Rating: 2
Thats exactly my point TomZ....

So basically, all the global warming nuts are blaming CO2 as being the main reason for increase in global temperatures...when in fact, they are blatently saying its not as evidence right here.

What this goes to show is that CO2 has absolutely nothing to do with global warming, if it even exists at all....but this is more of a war against "big oil" - which sounds to me like a personal agenda, not a betterment for all of society.

The whole "we need CO2 from somewhere else but oil" statement, and then trying to convince us that CO2 is in fact different depending on where it comes from, is absolutely ridiculous. Sooner or later, the fear mongers will go down.


RE: How this CO2 is different?
By feelingshorter on 12/2/2007 2:25:51 AM , Rating: 2
Well, this article just happens to to imply that if you read it that way.

What they are saying is that they are turning glycerol into hydrogen, when before, it would have been thrown away. So it is cleaner for the environment in one point of view. I'd rather get hydrogen fuel from it than having it sit in a land fill.


RE: How this CO2 is different?
By Oregonian2 on 12/3/2007 9:02:50 PM , Rating: 2
Why not use it to make sweeteners, health care products, etc as listed as to what it's good for anyway? Not like we'd ever have too much sweeteners.


RE: How this CO2 is different?
By djc208 on 12/2/2007 8:44:02 AM , Rating: 2
Because the CO2 released by processing the plant matter will be re-captured next year when the new crop of plant matter is grown to generate more fuel. It's carbon neutral because the gross amount of CO2 in the biosphere is unchanged. Burning fossil fuels releases CO2 that hadn't been part of the environment for many years.


RE: How this CO2 is different?
By masher2 (blog) on 12/2/2007 1:27:20 PM , Rating: 3
> "It's carbon neutral because the gross amount of CO2 in the biosphere is unchanged"

Not when you utilize biomass grown specifically for the purpose. Commercial crops use vast amounts of fertilizer (created from fossil fuels), along with fuel use to plant, grow, harvest and process the final material.

This is the reason that recent studies have shown that ethanol not only isn't "carbon neutral", but it actually releases more GHGs than does the use of gasoline.


RE: How this CO2 is different?
By djc208 on 12/2/2007 7:40:44 PM , Rating: 2
True, and a good point, but that's assuming you use some mix of natural and fossil fuels during this process. The ultimate goal of all this research is to replace as much fossil fuel as possible, eventually we'll have to replace all of it.

If the farm and industrial equipment and delivery vehicles all ran on biofuels, the energy sources for the processing were nuclear or natural, and natural fertilizers/farming methods used, then it would be a carbon neutral process.

Problem is these are all big ifs, and unlikely to happen quickly or soon. This also assumes you can get anywhere near a decent fuel/H2 yield from these crops. If 10% of the biomass actually becomes usable fuel products, by the time you factor in the energy requirements you mentioned you'd be lucky to have 50% of that fuel remaining. But these are first steps, and necessary ones if our quality of life is to be maintained after the finite fossil fuel sources are too scarce to support us.


CO2 is still CO2
By mdogs444 on 12/1/07, Rating: 0
RE: CO2 is still CO2
By Talcite on 12/1/2007 2:55:07 PM , Rating: 2
I see you failed gr 10 chemistry.

Hydrogen is the lightest of all gases, it naturally escapes our atmosphere because the earth's gravity isn't strong enough to hold it.

Also, I don't think you read the article. We're not going to have excess hydrogen because it is used as a reactant in the hydrogen fuel cell, yielding water as the product.

There's a million and a half uses for hydrogen, this process is great.

Anyways, you should learn a bit more before you start proclaiming global warming's false all over the place. Your post is perfect proof of how ignorant you are about the chemistry behind it.

Oh and the title's terrible. Gaseous CO2 is very different from liquid CO2 or carbonate ion (aqueous CO2). CO2(g) is not still CO2(l). You can store liquid CO2. Liquid CO2 is useful.

You really think CO2's the same? If I put you in a room with a tub of liquid CO2 you'd be fine. If I did the same thing with you in a room with enough gaseous CO2, you'd be dead. Also, try touching some gaseous CO2. No problem right? Now try it with some liquid CO2.

My point is that the filter they use in the process would never capture CO2 as a gas. They would either react it with another substance to form a manageable solid, or store it as a liquid. So CO2 is not just CO2.


RE: CO2 is still CO2
By Dreamwalker on 12/1/2007 3:20:52 PM , Rating: 2
"
1.)You really think CO2's the same?
2.)If I put you in a room with a tub of liquid CO2 you'd be fine. If I did the same thing with you in a room with enough gaseous CO2, you'd be dead.
3.)Also, try touching some gaseous CO2. No problem right? Now try it with some liquid CO2."

1.) yes it is
2.) wait few minutes and it would be the same as if you would turn up gaseous pipe of CO2
3.) touching CO2(s)? well, at ~-70°C I guess you would end with freezed fingers/hand(?) (at least I guess so, but I didn't have any chance to play with this stuff, so I'm not sure).

What you are describing is just the state of the chemical subject. CO2 is liquid at around -55°C and 5atm pressure. when you heat it up, lower the pressure, it vaporises.


RE: CO2 is still CO2
By Strunf on 12/1/2007 4:12:27 PM , Rating: 2
Just to point out that while I've never touched liquid CO2 I did touch liquid N2 at -195°C, the point is to not leave your hand or fingers in it long enough to freeze.

And there's people fooling around with solid CO2 at -80°C, just type dry ice on you tube...


RE: CO2 is still CO2
By Talcite on 12/1/2007 4:55:31 PM , Rating: 2
True, the first analogy was probably flawed. I was assuming there would be circulation of air, and a closed system. Under those conditions, the CO2(l) would reach equilibrium with CO2(g) at a certain point, and you'd be alive until the oxygen ran out.

My point is not that the states are different (they are though), but my point is that CO2 in a different state is easier to manage. There is no chance of liquid CO2 stored in a cylinder causing global warming or having a greenhouse effect.

And yes, I've worked with liquid and solid CO2 before. It's cold, and it'll give you some serious frostbite.


RE: CO2 is still CO2
By masher2 (blog) on 12/2/2007 1:23:57 PM , Rating: 1
> "Hydrogen is the lightest of all gases, it naturally escapes our atmosphere because the earth's gravity isn't strong enough to hold it."

At any given time, there are roughly 150 teragrams of hydrogen in our atmosphere. While some does escape into space, the larger sink is soil processes that absorb it.

And btw, this is no different than CO2, methane, or any other greenhouse gas. All have limited lifespans in the atmosphere.

> "I see you failed gr 10 chemistry...I put you in a room with a tub of liquid CO2 you'd be fine."

Err, liquid CO2 isn't possible at normal atmospheric pressures, regardless of what temperature you hold it at. You need between 40-70 atmospheres of pressure to create liquid CO2; no one's going to be sitting in a tub of it.


Now That's Irony
By Sahrin on 12/1/2007 1:21:07 PM , Rating: 4
Take the byproducts of the filthiest alternative energy source to make the storage mechanism of one of the clearnest.




Hooray for Earth!
By daftrok on 12/1/2007 1:35:05 PM , Rating: 1
Zim: Gir, Earth is our enemy.
Gir: ....I understand.




RE: Hooray for Earth!
By TomZ on 12/1/2007 4:00:04 PM , Rating: 2
^- Not so subtle attempt to earn a +6 rating from Kris using an obscure TV or movie quote. :o)


yay science!
By Whedonic on 12/1/2007 1:15:43 PM , Rating: 2
It's nice to occasionally see a real, genuine scientific breakthrough that may end up really helping mankind and the plane.




Not really the point
By djc208 on 12/2/2007 9:17:24 AM , Rating: 2
Most of the point behind hydrogen and bio-fuels isn't for environmental benefit, that's just a side effect (if you can get it).

The point was as an alternative energy storage/transfer medium. The goal is to get away from finite and unstable oil sources. No method of generating H2 is going to generate more energy than it takes to create, that's a simple law of thermodynamics. The point is that H2 created from steam generated in a coal or natural gas steam plant can be done using local energy sources.

Hence the term of having "a hydrogen economy".




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