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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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CO2 is still CO2
By mdogs444 on 12/1/2007 2:23:43 PM , Rating: 0
quote:
The process developed at Leeds turns this waste into clean hydrogen, water and carbon dioxide.


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?

Is it that because if CO2 is developed by them, it somehow has a different meaning to the world than CO2 developed not by them?

Whats going to happen when they try to convert everything to a "LEED" process - will then they complain about "unnatural" amounts of hydrogen in the atmosphere that is causing the next ice age, global cooling, or hell, responsible for a global fog?




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.


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