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To: Zerodown; Rick_Michael; Robert A. Cook, PE; dr_lew; patton; neverdem; secret garden; xsmommy; ...
Sustainable and efficient biohydrogen production via electrohydrogenesis

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.

65 posted on 11/13/2007 2:39:18 PM PST by neverdem (Call talk radio. We need a Constitutional Amendment for Congressional term limits. Let's Roll!)
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To: neverdem
This electrohydrogenic process thus provides a highly efficient route for producing hydrogen gas from renewable and carbon-neutral biomass resources.

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?

69 posted on 11/13/2007 3:57:01 PM PST by Myrddin
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