Posted on 09/17/2004 3:43:53 PM PDT by Indy Pendance
To efficiently operate a fuel cell, carbon monoxide has always been a major technical barrier. But now, chemical and biological engineers at the University of WisconsinMadison have not only cleared that barrierthey also found a method to capture carbon monoxide's energy.
To be useful in a power-generating fuel cell, hydrocarbons such as gasoline, natural gas, or ethanol must reform into a hydrogen-rich gas. A large, costly, and critical step to this process requires generating steam and forcing a reaction with carbon monoxide (CO). This process, called water-gas shift, produces hydrogen and carbon dioxide (CO2). Additional steps then must reduce the CO levels further before the hydrogen enters a fuel cell.
Researchers eliminated the water-gas shift reaction from the process, removing the need to transport and vaporize liquid water in the production of energy for portable applications.
The team, led by James Dumesic, professor of chemical and biological engineering, uses an environmentally benign polyoxometalate (POM) compound to oxidize CO in liquid water at room temperature. The compound not only removes CO from gas streams for fuel cells, but also converts the energy content of CO into a liquid that subsequently can power a fuel cell.
"CO has essentially as much energy as hydrogen," Dumesic said. "It has a lot of energy in it. If you take a hydrocarbon and partially oxidize it at high temperature, it primarily makes CO and hydrogen. Conventional systems follow that with a series of these 'water-gas shift' steps. Our discovery has the potential of eliminating those steps. Instead, you can send the CO through our process, which works efficiently at room temperature and takes the CO out of the gas to make energy."
The research team says the process is especially promising for producing electrical energy from renewable biomass-derived oxygenated hydrocarbonssuch as ethylene glycol derived from cornbecause these fuels generate H2 and CO in nearly equal amounts during catalytic decomposition. The hydrogen could directly go into a protonexchangemembrane fuel cell operating at 50% efficiency, and the remaining CO could convert to electricity via the new process.
For related information, go to www.isa.org/manufacturing_automation.
One paper published online proposes that the thermal gradient could be used for energy generation, H2 producton and liquefaction for storage. see link
Researchers Succeed In Fueling UpThe principle behind fuel cells is not new-it was discovered in 1839... Basically, a fuel cell is a device-think of it as a high-tech battery-that converts the energy of a fuel (hydrogen, natural gas, etc.) and an oxidant (air or oxygen) into useable electricity... There are no moving parts and it produces little noise. Unlike traditional combustion engines that currently dominate the energy market, fuel cells do not produce any particulate matter, nitrogen or sulfur oxides; when fueled by pure hydrogen, they have only heat and water as by-products... To date, hydrogen has been the conventional fuel for a fuel cell. But practical generation and storage of hydrogen has been a problem-it's expensive and inefficient. The model developed by Gorte's team aims to get around this dilemma... Previous attempts to use hydrocarbon fuels to run a solid-oxide fuel cell failed because the electrochemical process that generates electricity caused a buildup of carbon, which ruined the cell. In a solid-oxide fuel cell, oxygen anions are transported through an oxide membrane and react with the fuel at the anode... The Penn researchers were looking for an anode material that did not result in fouling... Eventually, they settled on a composite of copper and ceria. Ceria is an important catalytic component of automotive catalysis, which is why the researchers focused on its properties... Says Gorte, "Running a car is a transient process and you've got to have a pretty big fuel cell to power it, something on the order of 50kw as opposed to a 5kw cell to power a house, for instance." ...At least one major automotive manufacturer is seriously studying this technology... Their work has generated a great deal of excitement and was touted in Nature magazine (3/16/00). Professor Gorte has been interviewed by MSNBC.
by Jane BrooksFuel-cell future for gasoline?"We've demonstrated that we can run a fuel cell directly on hydrocarbons like gasoline and diesel," researcher Ray Gorte told MSNBC. "In the past, everyone assumed you had to use hydrogen." ...The new process not only gets around the problem of delivering and storing hydrogen, Gorte says, it means a fuel cell that produces "less carbon dioxide for a given amount of energy" than other fuel cells because higher efficiency can be achieved... [I]t could provide a valuable interim technology that's easier to deploy and still provide much cleaner and higher mileage than internal combustion engines... Gorte, head of chemical engineering at the University of Pennsylvania, sees the research as a "breakthrough," saying an earlier attempt to use gasoline essentially required putting "a refinery in your trunk" to get the hydrogen... Gorte's team used a "solid oxide fuel cell," while others have tended to focus on "proton-exchange membranes." ...One hitch is that the cell is sensitive to sulfur, so that gasoline would have to be cleaned further to make it a viable fuel... Gorte is optimistic about its potential, saying his team hopes to work with a major car company that has created a solid oxide fuel cell division. He would not identify the company, saying he wasn't sure if it was willing to go public yet... Kevin Kendall, a chemical engineer at Britain's University of Birmingham, writes in a Nature article accompanying the study that while hydrogen is "the ultimate clean power source of the future" it is still expensive to extract it, difficult to store and prone to explosion.
by Miguel Llanos
March 15, 2000Coal-to-liquid solution for energy woesAmid continuing violence in the Middle East, the issue of energy security is again on the front burner. With oil prices rising to a peak of US$40 (S$68) a barrel, countries have been looking at alternative energy with a greater urgency. This heightened sense of urgency, fortunately, has come at a time when there is evidence that a new approach using existing resources and technology can provide alternative energy to many countries.
by David Dapice
StraitsTimes
July 19, 2004
Posted on 07/20/2004 9:27:15 AM PDT by Baby Bear
A glimmer of good news recently appeared: China signed an agreement with Sasol, a South African energy and chemicals firm, to build two coal-to-liquid fuel plants in China. These plants, costing US$3 billion each, are reported by the Financial Times to jointly produce 60 million tonnes of liquid fuel (440 million barrels) a year. Since China imported 100 million tonnes of oil last year, these plants would give China much control over its domestic energy situation, though its demand is growing fast.Toyota Shines at Tokyo Show With Gasoline-Fuel Cell SUV"The company, fuel cell r&d development partner with General Motors, unveiled its new FCHV-5 at the 35th Tokyo Motor Show Oct. 27-Nov.9, the fifth-generation experimental vehicle in its fuel cell hybrid series. The new vehicle employs a reformer to extract hydrogen from a still to be developed 'clean hydrocarbon' fuel... 'Clean' hydrocarbon fuel is a euphemism for gasoline from which sulfur has been removed."
IMPORTANT
There is no mention AT ALL in this article about automotive fuel cells. The type of fuel cell that is being developed for automotive uses is a PEM type fuel cell.
BUT THIS ARTICLE HAS NOTHING TO DO WITH PEM FUEL CELLS
The PEM fuel cell uses a membrane as an electrolyte. This membrane is highly sensitive to impurities - the impurities accumulate within the membrane and degrade its performance accordingly. PEM fuel cells CANNOT use reformed fuel because very minor amounts of sulfur and chloride will quickly degrade the cell.
The article is still important though - for PAFC type fuel cells. PAFC fuel cells have found good use as a power supply for large buildings (factories, apartment complexes, etc). These devices are about the size of a small one car garage. Such PAFC fuel cell units have built in reformers, and yes, CO removal is a significant part of the reformer.
This is good news for fuel cells, BUT IT HAS NOTHING TO DO WITH CARS
Perhaps, someone has learned from history and / or has something on the drawing boards?
George W. Bush will be reelected by a margin of at least ten per cent
George W. Bush will be reelected by a margin of at least ten per cent
How Long Will the Oil Age Last?
Popular Science ^ | August 2004 | Kevin Kelleher
Posted on 07/31/2004 1:48:26 PM PDT by SunkenCiv
http://www.freerepublic.com/focus/f-news/1182542/posts
Kerry's Energy Agenda: Higher prices, more foreign dependency.
National Review Online ^ | August 12, 2004 | Cesar Conda
Posted on 08/14/2004 6:06:35 AM PDT by xsysmgr
http://www.freerepublic.com/focus/f-news/1191456/posts
Report Questions Bush Plan for Hydrogen-Fueled Cars
NY Times ^ | February 6, 2004 | MATTHEW L. WALD
Posted on 02/07/2004 6:00:36 PM PST by neverdem
http://www.freerepublic.com/focus/f-news/1073676/posts
The Chinese Navy is doing a pretty good job of putting their own subs on the bottom all by themselves.
For example, here's a study on just exactly that.
Back to Coal, Why Utilities Must Reconsider This Cheap, Plentiful Fuel
We could ween off of the oil import, put lots of miners and truckers back to work and then work on the longer term solutions of Fuel Cells.
Thanks for the ping.
George W. Bush will be reelected by a margin of at least ten per cent
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