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Re: The great hydrogen energy scam
Posted by Dr Fred Mbogo on 6/18/04

    Sir:

    'Green energy' is a bunch of crap. This concept will never put a
    dent in our growing dependency on fossil fuels. Extracting energy
    from Windmill farms and making energy from compost pits is never
    going to replace fossil fules.

    Check out the site below to read about the "great hydrogen energy
    scam!!"


    On 6/18/04, Dan wrote:
    > On 6/18/04, Dr Fred Mbogo wrote:
    >> Sir:
    >>
    >> There is NO excess hydroelectric power in the Columbia River
    >> Basin or anywhere in this country. That power is ALREADY BEING
    >> USED to generate electricity. What is not being immediately
    >> used to generate electricity is being stored in dams behind
    >> the hydro generation plant for future use. Electricity that is
    >> produced by hydroelectric generators (or any other electric
    >> generating means) can be used for any purpose, including
    >> separating free hydrogen from water molecules by electrolysis.
    >> But the laws of physics ("conservation of energy," et al) say
    >> that whatever electrical energy is used for separating
    >> hydrogen CANNOT be used for any other purpose. Once that
    >> hydrogen atom is separated, the energy that was needed to
    >> accomplish that is now in the hydrogen atom as 'chemical
    >> potential energy' or whatever, it ain't still available to run
    >> your damn microwave like it otherwise could have. The sad fact
    >> is that extracting hydrogen from water CONSUMES ENERGY.
    >
    > They've been working on co-energy projects for years.
    >
    > BTW, I did not write the article. Tell it to the researchers.
    >
    > June 26, 2003
    > Low Cost Biomass Hydrogen Catalyst Discovered
    > Researchers at the University of Wisconsin in Madison have
    > discovered a much lower cost catalyst for producing hydrogen
    > from organic matter.
    >
    > MADISON – It is thousands of times less expensive than platinum
    > and works nearly as well.
    >
    > Writing this week in the journal Science (June 27) University
    > of Wisconsin-Madison chemical and biological engineers report
    > the discovery of a nickel-tin catalyst that can replace the
    > precious metal platinum in a new, environmentally sustainable,
    > greenhouse-gas-neutral, low-temperature process for making
    > hydrogen fuel from plants.
    >
    > The new catalyst, together with a second innovation that
    > purifies hydrogen for use in hydrogen fuel cells, offers new
    > opportunities toward the transition of a world economy based on
    > fossil fuels to one based on hydrogen produced from renewable
    > resources.
    >
    > James Dumesic, a professor of chemical and biological
    > engineering, and graduate students George Huber and John
    > Shabaker describe testing more than 300 materials to find a
    > nickel-tin-aluminum combination that reacts with biomass-
    > derived oxygenated hydrocarbons to produce hydrogen and carbon
    > dioxide without producing large amounts of unwanted methane.
    >
    > "Platinum is very effective but it's also very expensive," says
    > Dumesic. "It's also problematic for large-scale power
    > production because platinum is already in demand for use as
    > anode and cathode materials in hydrogen fuel cells. We knew
    > nickel was very active, but it allowed reaction to continue
    > beyond hydrogen producing methane. We found that adding tin to
    > what's known as a Raney-Nickel catalyst decreased the rate of
    > methane formation without compromising the rate of hydrogen
    > production."
    >
    > Dumesic, research scientist Randy Cortright (now at Virent
    > Energy Systems) and graduate student Rupali Davda first
    > reported the catalytic reforming process for hydrogen
    > production in the Aug. 29, 2002 issue of the journal Nature.
    >
    > The simple, single-step process employs temperature, pressure
    > and a catalyst to convert hydrocarbons such as glucose, the
    > same energy source used by most plants and animals, into
    > hydrogen, carbon dioxide, and gaseous alkanes with hydrogen
    > constituting 50 percent of the products. More refined molecules
    > such as ethylene glycol and methanol are almost completely
    > converted to hydrogen and carbon dioxide. Because plants grown
    > as fuel crops absorb the carbon dioxide released by the system,
    > the process is greenhouse-gas neutral.
    >
    > Platinum is too expensive.
    >
    > The precious metal platinum (Pt) is well known to be an
    > excellent catalyst in a number of chemical reactions. It is one
    > component in a car's catalytic converter, for example, that
    > helps remove toxins from automobile exhaust. Yet, platinum is
    > rare and very expensive, costing more than $17 per gram (about
    > $8,000 per pound).
    >
    > Catalytic platinum (Pt) and nickel (Ni) stand out from other
    > metals (such as copper or iron) because they process reaction
    > molecules much faster. But pure nickel, unlike platinum,
    > recombines the hydrogen product with carbon atoms to make
    > methane, a common greenhouse gas. Dumesic and his colleagues
    > tested over 300 catalysts to find one that could compete with
    > platinum and perform in the APR process. Using a specially
    > designed reactor that can test 48 samples at one time, the team
    > finally found a match in a modified version of what researchers
    > call a Raneynickel catalyst, named after Murray Raney, who
    > first patented the alloy in 1927.
    >
    > Raney-nickel is a porous catalyst made of about 90 percent
    > nickel (Ni) and 10 percent aluminum (Al). While Raney-nickel
    > proved somewhat effective at separating hydrogen from biomass-
    > derived molecules, the researchers improved the material's
    > effectiveness by adding more tin (Sn), which stops the
    > production of methane and instead generates more hydrogen.
    > Relative to other catalysts, the Raney-NiSn can perform for
    > long time periods (at least 48 hours) and at lower temperatures
    > (roughly 225 degrees Celsius).
    >
    > According to Dumesic, a substitute for platinum catalysts is
    > essential for the success of hydrogen technology. "We had to
    > find a substitute for platinum in our APR process for
    > production of hydrogen, since platinum is rare and also
    > employed in the anode and cathode materials of hydrogen fuel
    > cells to be used in products such as cars or portable
    > computers," he said.
    >
    > While this is an important advance by itself it does not make
    > biomass a viable major energy source. The problem with growing
    > crops for biomass is that it takes energy to make and transport
    > the fertilizer, run tractors, run irrigation equipment,
    > harvest, transport, and so on. It remains to be seen whether
    > there is a crop that will yield enough biomass energy to make
    > it worthwhile.
    >
    > This catalyst may be useful on smaller scales in places where
    > there is already a great amount of biomass waste being
    > produced. For instance, the processing of existing crops
    > produces biomass waste. Equipment to convert that biomass waste
    > into useful hydrogen energy could be installed next to
    > agricultural product processing facilities if this new catalyst
    > turns out to work well in industrial use. Still, all the
    > existing biomass waste is not sufficient as an energy source to
    > replace much of the currently consumed fossil fuels.
    >
    > Other enabling technologies such as fuel cells need to mature
    > ot make hydrogen a more useful energy source once it has been
    > produced. Those advances will come with time. What strikes me
    > as less certain is whether biomass will ever become a major
    > energy source for producing hydrogen. Plants have to be
    > planted, tended, harvested, and processed. They are vulnerable
    > to insects and droughts. They do not convert most of the light
    > that hits them into stored chemical energy.
    >
    > There are competing approaches that may be cheaper in the
    > longer run. Advances in nanotechnology will eventually yield
    > photovoltaic materials that will be cheap to produce. Then the
    > electricity from the photovoltaics will could be used to run
    > hydrolysis reactions to produce hydrogen from water. Also, some
    > materials may be found that can absorb light to drive a direct
    > catalysis reaction to produce hydrogen from water without first
    > producing electricity. Such materials would probably be more
    > efficient than plants at converting sunlight to energy and
    > would even be able to do so all year around (albeit at lower
    > rates during the shorter days of the year).
    >
    > Update: Some Tufts researchers have also recently discovered a
    > way to reduce the amount of precious metals used as catalysts
    > to make hydrogen.
    >
    > "A lot of people have spent a lot of time studying the
    > properties of gold and platinum nanoparticles that are used to
    > catalyze the reaction of carbon monoxide with water to make
    > hydrogen and carbon dioxide," said Maria Flytzani-
    > Stephanopoulos, professor of chemical and biological
    > engineering at Tufts and the lead researcher of the
    > project. "We find that for this reaction over a cerium oxide
    > catalyst carrying the gold or ...[Message truncated]


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