Posted on 11/12/2007 10:45:42 PM PST by Rick_Michael
CHICAGO (AFP) - US researchers have developed a method of producing hydrogen gas from biodegradable organic material, potentially providing an abundant source of this clean-burning fuel, according to a study released Monday.
The technology offers a way to cheaply and efficiently generate hydrogen gas from readily available and renewable biomass such as cellulose or glucose, and could be used for powering vehicles, making fertilizer and treating drinking water.
Numerous public transportation systems are moving toward hydrogen-powered engines as an alternative to gasoline, but most hydrogen today is generated from nonrenewable fossil fuels such as natural gas.
The method used by engineers at Pennsylvania State University however combines electron-generating bacteria and a small electrical charge in a microbial fuel cell to produce hydrogen gas.
Microbial fuel cells work through the action of bacteria which can pass electrons to an anode. The electrons flow from the anode through a wire to the cathode producing an electric current. In the process, the bacteria consume organic matter in the biomass material.
An external jolt of electricity helps generate hydrogen gas at the cathode.
In the past, the process, which is known as electrohydrogenesis, has had poor efficiency rates and low hydrogen yields.
But the researchers at Pennsylvania State University were able to get around these problems by chemically modifying elements of the reactor.
In laboratory experiments, their reactor generated hydrogen gas at nearly 99 percent of the theoretical maximum yield using aetic acid, a common dead-end product of glucose fermentation.
"This process produces 288 percent more energy in hydrogen than the electrical energy that is added in the process," said Bruce Logan, a professor of environmental engineering at Penn State.
The technology is economically viable now, which gives hydrogen an edge over another alternative biofuel which is grabbing more headlines, Logan said.
"The energy focus is currently on ethanol as a fuel, but economical ethanol from cellulose is 10 years down the road," said Logan.
"First you need to break cellulose down to sugars and then bacteria can convert them to ethanol."
One of the immediate applications for this technology is to supply the hydrogen that is used in fuel cell cars to generate the electricity that drives the motor, but it could also can be used to convert wood chips into hydrogen to be used as fertilizer.
The study appears in the Proceedings of the National Academy of Sciences.
Driving into Georgia the first time, my wife commented on the interesting aesthetics of what looked like a dark green blanket draped over the forests. “That’s pretty neat” she said. “That’s Kudzu. Everything under it is dead because the light is blocked out” I replied. Pause. “Oh gosh that’s scary” she said, squirming.
Why doesn't George Bush encourage incentives for oil companies to build more refining capacity? I voted for a genuine Texas Awlbidnessman, complete with cowboy boots, with just such a hope in mind.
I don't want to be rude,
But there sure is plenty of crude
the Whole Awl Bidness be out of kilter
Just because the big boys play too rough
won't filter enough of that stuff
To keep the price low;
the economy on the go
Gettin' more combustion out of domestic production.
The aether bunny, and a nappy hoe, are two examples of fuzzy logic.
Kudzu and Cottonwoods.
Hydrogen gas has tremendous potential as an environmentally acceptable energy carrier for vehicles, but most hydrogen is generated from nonrenewable fossil fuels such as natural gas. Here, we show that efficient and sustainable hydrogen production is possible from any type of biodegradable organic matter by electrohydrogenesis. In this process, protons and electrons released by exoelectrogenic bacteria in specially designed reactors (based on modifying microbial fuel cells) are catalyzed to form hydrogen gas through the addition of a small voltage to the circuit. By improving the materials and reactor architecture, hydrogen gas was produced at yields of 2.01–3.95 mol/mol (50–99% of the theoretical maximum) at applied voltages of 0.2 to 0.8 V using acetic acid, a typical dead-end product of glucose or cellulose fermentation. At an applied voltage of 0.6 V, the overall energy efficiency of the process was 288% based solely on electricity applied, and 82% when the heat of combustion of acetic acid was included in the energy balance, at a gas production rate of 1.1 m3 of H2 per cubic meter of reactor per day. Direct high-yield hydrogen gas production was further demonstrated by using glucose, several volatile acids (acetic, butyric, lactic, propionic, and valeric), and cellulose at maximum stoichiometric yields of 54–91% and overall energy efficiencies of 64–82%. This electrohydrogenic process thus provides a highly efficient route for producing hydrogen gas from renewable and carbon-neutral biomass resources.
The link says the pdf is free. IIRC, goats were taking care of the kudzu in Tennessee.
Acetic acid is vinegar.
We could easily manufacture the stuff by the boatload - near cheap as dirt.
Correct me if I’m wrong, but acetic acid is merely vinegar.
Lets biologically engineer a kudzu to have a giant venus flytrap appendage and then air drop seeds over china and see what happens!
When I hear discussion of a "renewable" resource based on biomass input, I'm reminded of the stupidity of the current corn to ethanol activity. Ethanol is a poor replacement for gasoline. Turning human edible food into a crappy replacement for gasoline is a bad idea. What "biomass" is targeted as the input to this process? Will it affect food prices or skew farming practices away from food producing activities?
I suggest you visit the Air Products website and check out the hydrogen section to get an idea of how "small" the bottled hydrogen market really is.
"There is not enough energy in a bottle of hydrogen to be feasable for fuel use."
Depends on how you use it as fuel, now doesn't it.
"The hydrogen bottles are designed for hydrogen. Black pipe infrastructure is not.
Hydrogen bottles ARE "black pipe" (i.e. a carbon steel alloy). I haven't found yet exactly which alloy they use, but I can guarantee you that hydrogen bottles are NOT stainless steel, because their "outsides" DO rust where the paint is chipped.
"Hydrogen has many disadvantages and only one advantage. If you believe that man made CO2 is causing global warming then hydrogen allows you to move the CO2 production from the tail pipe to a plant where you can capture it.
ANYTHING that increases the availability of energy for mankind is a good thing. If hydrogen production using bacteria and biomass helps do that, then that's a good thing.
Hydrogen is one of the earliest "industrial gases" that mankind ever used in large quantities--starting as "town gas" (~50% hydrogen) produced from low-temperature gasification of coal which originated around 1802, and distributed by, guess what, BLACK PIPE plumbing. We've been using hydrogen on an industrial scale ever since. We know how to handle it with sufficient safety. And I get damned tired of scaremongers like you constantly harping on "how dangerous" it is.
another could be breakthrough
You have a good point about power being a consideration, but this point doesn't necessarily follow. If the plant is cheap enough more scale can overcome the lesser power output.
What "biomass" is targeted as the input to this process? Will it affect food prices or skew farming practices away from food producing activities?
"Here, we show that efficient and sustainable hydrogen production is possible from any type of biodegradable organic matter by electrohydrogenesis."
I didn't read the pdf, but I got the impression it could use almost anything with a biological origin.
If we can get energy independence, it’s a three for one deal. It defunds a lot of bad guys, it helps our current accounts deficit, aka trade deficit, and it stops the drop in the value of the US dollar.
I don't buy it. The dollar is falling because the Fed is printing money at a furious pace and the government is spending money far in excess of income.
I didn't read the pdf, but I got the impression it could use almost anything with a biological origin.
Useless eaters? Biodiesel already has a line on a viable conversion of specific kinds of biological refuse. There are plants online. It's practical now, yet it hardly makes a dent in our energy demands.
That's part of the problem, but oil is priced in U.S. dollars, IIRC. Everyone accumulating excess U.S. dollars overseas reduces their demand and value as a reserve currency.
Growing corn is cheap, but there isn't enough arable land on the planet to replace gasoline with E85. How much hydrogen is required to replace 1 gallon of gasoline for an equivalent amount of useful travel in an average car? How much gasoline do we consume as a nation daily? How big does this new hydrogen plant have to be to replace 10% of our daily use? How long will it take to install adequate infrastructure all over the U.S. to make travel in a hydrogen car even possible?
It has been. Don't count on it remaining that way. There are already moves to switch to the Euro. That nearly happened just before we returned to Iraq in 2003.
>>and goes through metal pipes without causing metal to become brittle.
The gross ignorance of hydrogen embrittlement of steel is rampant. Even here at Free Republic, but especially so in the MSM.
Those are all good questions (to which I don’t have the answers). I’m skeptical of the so-called hydrogen economy too. I was just replying to your point about the power output of the hydrogen generating facility being an important consideration but that slower power can be offset by more generating plant if it’s cheap enough.
I think hydrogen is just another boondoggle. It definitely has an appropriate application. It is perfect for use on a space station where the end products need to be non-toxic to the crew. In a terrestrial application, it only moves the location of toxic emissions to the hydrogen production facility instead of being local to the end user of the energy product. There is no net environmental gain and there is a significant loss of energy potential in the conversion process.
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